Changeset 93b6fcc in sasview


Ignore:
Timestamp:
Apr 23, 2014 1:41:21 PM (11 years ago)
Author:
smk78
Branches:
master, ESS_GUI, ESS_GUI_Docs, ESS_GUI_batch_fitting, ESS_GUI_bumps_abstraction, ESS_GUI_iss1116, ESS_GUI_iss879, ESS_GUI_iss959, ESS_GUI_opencl, ESS_GUI_ordering, ESS_GUI_sync_sascalc, costrafo411, magnetic_scatt, release-4.1.1, release-4.1.2, release-4.2.2, release_4.0.1, ticket-1009, ticket-1094-headless, ticket-1242-2d-resolution, ticket-1243, ticket-1249, ticket885, unittest-saveload
Children:
6386cd8
Parents:
58eccf6
Message:

More updates by SMK

File:
1 edited

Legend:

Unmodified
Added
Removed
  • src/sans/models/media/model_functions.rst

    r58eccf6 r93b6fcc  
    3434.. |psi| unicode:: U+03C8 
    3535.. |omega| unicode:: U+03C9 
     36.. |biggamma| unicode:: U+0393 
    3637.. |bigdelta| unicode:: U+0394 
    37 .. |biggamma| unicode:: U+0393 
     38.. |bigzeta| unicode:: U+039E 
    3839.. |bigpsi| unicode:: U+03A8 
    3940.. |drho| replace:: |bigdelta|\ |rho| 
     
    6263.. Actual document starts here... 
    6364 
     65This is xi, |xi| 
     66 
     67This is zeta, |zeta| 
     68 
    6469SasView Model Functions 
    6570======================= 
     
    211216 
    212217- AbsolutePower_Law_ 
    213 - BEPolyelectrolyte 
    214 - BroadPeakModel 
    215 - CorrLength 
    216 - DABModel 
    217 - Debye 
    218 - FractalModel 
    219 - FractalCoreShell 
    220 - GaussLorentzGel 
    221 - Guinier 
    222 - GuinierPorod 
    223 - Lorentz 
    224 - MassFractalModel 
    225 - MassSurfaceFractal 
     218- BEPolyelectrolyte_ 
     219- BroadPeakModel_ 
     220- CorrLength_ 
     221- DABModel_ 
     222- Debye_ 
     223- FractalModel_ 
     224- FractalCoreShell_ 
     225- GaussLorentzGel_ 
     226- Guinier_ 
     227- GuinierPorod_ 
     228- Lorentz_ 
     229- MassFractalModel_ 
     230- MassSurfaceFractal_ 
    226231- PeakGaussModel 
    227232- PeakLorentzModel 
     
    231236- RPA10Model 
    232237- StarPolymer 
    233 - SurfaceFractalModel 
    234 - Teubner Strey 
     238- SurfaceFractalModel_ 
     239- TeubnerStrey_ 
    235240- TwoLorentzian 
    236241- TwoPowerLaw 
     
    275280 
    276281*Small-Angle Scattering of X-Rays* 
    277 A. Guinier and G. Fournet 
     282A Guinier and G Fournet 
    278283John Wiley & Sons, New York (1955) 
    279284 
    280 P. Stckel, R. May, I. Strell, Z. Cejka, W. Hoppe, H. Heumann, W. Zillig and H. Crespi 
     285P Stckel, R May, I Strell, Z Cejka, W Hoppe, H Heumann, W Zillig and H Crespi 
    281286*Eur. J. Biochem.*, 112, (1980), 411-417 
    282287 
    283 G. Porod 
     288G Porod 
    284289in *Small Angle X-ray Scattering* 
    285 (editors) O. Glatter and O. Kratky 
     290(editors) O Glatter and O Kratky 
    286291Academic Press (1982) 
    287292 
    288293*Structure Analysis by Small-Angle X-Ray and Neutron Scattering* 
    289 L.A. Feigin and D. I. Svergun 
     294L.A Feigin and D I Svergun 
    290295Plenum Press, New York (1987) 
    291296 
    292 S. Hansen 
     297S Hansen 
    293298*J. Appl. Cryst.* 23, (1990), 344-346 
    294299 
    295 S.J. Henderson 
     300S J Henderson 
    296301*Biophys. J.* 70, (1996), 1618-1627 
    297302 
    298 B.C. McAlister and B.P. Grady, B.P 
     303B C McAlister and B P Grady 
    299304*J. Appl. Cryst.* 31, (1998), 594-599 
    300305 
    301 S.R. Kline 
     306S R Kline 
    302307*J Appl. Cryst.* 39(6), (2006), 895 
    303308 
     
    356361REFERENCE 
    357362 
    358 A. Guinier and G. Fournet, *Small-Angle Scattering of X-Rays*, John Wiley and Sons, New York, (1955) 
     363A Guinier and G. Fournet, *Small-Angle Scattering of X-Rays*, John Wiley and Sons, New York, (1955) 
    359364 
    360365*2.1.1.2. Validation of the SphereModel* 
     
    368373The parameters were set to: Scale=1.0, Radius=60 |Ang|, Contrast=1e-6 |Ang^-2|, and Background=0.01 |cm^-1|. 
    369374 
    370 *2013/09/09 and 2014/01/06 - Description reviewed by S. King and P. Parker.* 
     375*2013/09/09 and 2014/01/06 - Description reviewed by S King and P Parker.* 
    371376 
    372377 
     
    421426REFERENCE 
    422427 
    423 N. W. Ashcroft and D. C. Langreth, *Physical Review*, 156 (1967) 685-692 
     428N W Ashcroft and D C Langreth, *Physical Review*, 156 (1967) 685-692 
    424429[Errata found in *Phys. Rev.* 166 (1968) 934] 
    425430 
     
    484489REFERENCE 
    485490 
    486 M. Stieger, J. S. Pedersen, P. Lindner, W. Richtering, *Langmuir*, 20 (2004) 7283-7292 
     491M Stieger, J. S Pedersen, P Lindner, W Richtering, *Langmuir*, 20 (2004) 7283-7292 
    487492 
    488493 
     
    541546REFERENCE 
    542547 
    543 K. Larson-Smith, A. Jackson, and D.C. Pozzo, *Small angle scattering model for Pickering emulsions and raspberry* 
     548K Larson-Smith, A Jackson, and D C Pozzo, *Small angle scattering model for Pickering emulsions and raspberry* 
    544549*particles*, *Journal of Colloid and Interface Science*, 343(1) (2010) 36-41 
    545550 
     
    592597REFERENCE 
    593598 
    594 A. Guinier and G. Fournet, *Small-Angle Scattering of X-Rays*, John Wiley and Sons, New York, (1955) 
     599A Guinier and G Fournet, *Small-Angle Scattering of X-Rays*, John Wiley and Sons, New York, (1955) 
    595600 
    596601*2.1.5.2. Validation of the core-shell sphere model* 
     
    726731REFERENCE 
    727732 
    728 S. King, P. Griffiths, J. Hone, and T. Cosgrove, *SANS from Adsorbed Polymer Layers*, 
     733S King, P Griffiths, J. Hone, and T Cosgrove, *SANS from Adsorbed Polymer Layers*, 
    729734*Macromol. Symp.*, 190 (2002) 33-42 
    730735 
     
    774779REFERENCE 
    775780 
    776 B. Cabane, *Small Angle Scattering Methods*, in *Surfactant Solutions: New Methods of Investigation*, Ch.2, 
    777 Surfactant Science Series Vol. 22, Ed. R. Zana and M. Dekker, New York, (1987). 
     781B Cabane, *Small Angle Scattering Methods*, in *Surfactant Solutions: New Methods of Investigation*, Ch.2, 
     782Surfactant Science Series Vol. 22, Ed. R Zana and M Dekker, New York, (1987). 
    778783 
    779784 
     
    893898REFERENCE 
    894899 
    895 L. A. Feigin and D. I. Svergun, *Structure Analysis by Small-Angle X-Ray and Neutron Scattering*, 
     900L A Feigin and D I Svergun, *Structure Analysis by Small-Angle X-Ray and Neutron Scattering*, 
    896901Plenum Press, New York, (1987). 
    897902 
     
    953958REFERENCE 
    954959 
    955 A. Guinier and G. Fournet, *Small-Angle Scattering of X-Rays*, John Wiley and Sons, New York, (1955) 
     960A Guinier and G. Fournet, *Small-Angle Scattering of X-Rays*, John Wiley and Sons, New York, (1955) 
    956961 
    957962 
     
    10821087REFERENCE 
    10831088 
    1084 L. A. Feigin and D. I. Svergun, *Structure Analysis by Small-Angle X-Ray and Neutron Scattering*, 
     1089L A Feigin and D I Svergun, *Structure Analysis by Small-Angle X-Ray and Neutron Scattering*, 
    10851090Plenum Press, New York, (1987) 
    10861091 
     
    11281133REFERENCE 
    11291134 
    1130 A. V. Dobrynin, M. Rubinstein and S. P. Obukhov, *Macromol.*, 29 (1996) 2974-2979 
     1135A V Dobrynin, M Rubinstein and S P Obukhov, *Macromol.*, 29 (1996) 2974-2979 
    11311136 
    11321137 
     
    11931198REFERENCE 
    11941199 
    1195 R. Schweins and K. Huber, *Particle Scattering Factor of Pearl Necklace Chains*, *Macromol. Symp.* 211 (2004) 25-42 2004 
     1200R Schweins and K Huber, *Particle Scattering Factor of Pearl Necklace Chains*, *Macromol. Symp.* 211 (2004) 25-42 2004 
    11961201 
    11971202 
     
    13421347REFERENCE 
    13431348 
    1344 L. A. Feigin and D. I. Svergun, *Structure Analysis by Small-Angle X-Ray and Neutron Scattering*, Plenum Press, 
     1349L A Feigin and D I Svergun, *Structure Analysis by Small-Angle X-Ray and Neutron Scattering*, Plenum Press, 
    13451350New York, (1987) 
    13461351 
     
    14271432REFERENCE 
    14281433 
    1429 H. Kaya, *J. Appl. Cryst.*, 37 (2004) 223-230 
    1430  
    1431 H. Kaya and N-R deSouza, *J. Appl. Cryst.*, 37 (2004) 508-509 (addenda and errata) 
     1434H Kaya, *J. Appl. Cryst.*, 37 (2004) 223-230 
     1435 
     1436H Kaya and N-R deSouza, *J. Appl. Cryst.*, 37 (2004) 508-509 (addenda and errata) 
    14321437 
    14331438 
     
    16121617REFERENCE 
    16131618 
    1614 L. A. Feigin and D. I. Svergun, *Structure Analysis by Small-Angle X-Ray and Neutron Scattering*, Plenum, 
     1619L A Feigin and D I Svergun, *Structure Analysis by Small-Angle X-Ray and Neutron Scattering*, Plenum, 
    16151620New York, (1987) 
    16161621 
     
    16721677REFERENCE 
    16731678 
    1674 J. S. Pedersen and P. Schurtenberger. *Scattering functions of semiflexible polymers with and without excluded volume* 
     1679J S Pedersen and P Schurtenberger. *Scattering functions of semiflexible polymers with and without excluded volume* 
    16751680*effects*. *Macromolecules*, 29 (1996) 7602-7612 
    16761681 
    16771682Correction of the formula can be found in 
    16781683 
    1679 W-R Chen, P. D. Butler and L. J. Magid, *Incorporating Intermicellar Interactions in the Fitting of SANS Data from* 
     1684W R Chen, P D Butler and L J Magid, *Incorporating Intermicellar Interactions in the Fitting of SANS Data from* 
    16801685*Cationic Wormlike Micelles*. *Langmuir*, 22(15) 2006 6539–6548 
    16811686 
     
    17601765REFERENCE 
    17611766 
    1762 J. S. Pedersen and P. Schurtenberger. *Scattering functions of semiflexible polymers with and without excluded volume* 
     1767J S Pedersen and P Schurtenberger. *Scattering functions of semiflexible polymers with and without excluded volume* 
    17631768*effects*. *Macromolecules*, 29 (1996) 7602-7612 
    17641769 
    17651770Correction of the formula can be found in 
    17661771 
    1767 W-R Chen, P. D. Butler and L. J. Magid, *Incorporating Intermicellar Interactions in the Fitting of SANS Data from* 
     1772W R Chen, P D Butler and L J Magid, *Incorporating Intermicellar Interactions in the Fitting of SANS Data from* 
    17681773*Cationic Wormlike Micelles*. *Langmuir*, 22(15) 2006 6539–6548 
    17691774 
     
    18231828REFERENCE 
    18241829 
    1825 L. A. Feigin and D. I. Svergun, *Structure Analysis by Small-Angle X-Ray and Neutron Scattering*, Plenum Press, 
     1830L A Feigin and D I Svergun, *Structure Analysis by Small-Angle X-Ray and Neutron Scattering*, Plenum Press, 
    18261831New York, (1987) 
    18271832 
     
    19111916REFERENCE 
    19121917 
    1913 H. Kaya, *J. Appl. Cryst.*, 37 (2004) 37 223-230 
    1914  
    1915 H. Kaya and N-R deSouza, *J. Appl. Cryst.*, 37 (2004) 508-509 (addenda and errata) 
     1918H Kaya, *J. Appl. Cryst.*, 37 (2004) 37 223-230 
     1919 
     1920H Kaya and N R deSouza, *J. Appl. Cryst.*, 37 (2004) 508-509 (addenda and errata) 
    19161921 
    19171922 
     
    19982003REFERENCE 
    19992004 
    2000 A. Guinier and G. Fournet, *Small-Angle Scattering of X-Rays*, John Wiley and Sons, New York, 1955 
    2001  
    2002 O. Kratky and G. Porod, *J. Colloid Science*, 4, (1949) 35 
    2003  
    2004 J. S. Higgins and H. C. Benoit, *Polymers and Neutron Scattering*, Clarendon, Oxford, 1994 
     2005A Guinier and G Fournet, *Small-Angle Scattering of X-Rays*, John Wiley and Sons, New York, 1955 
     2006 
     2007O Kratky and G Porod, *J. Colloid Science*, 4, (1949) 35 
     2008 
     2009J S Higgins and H C Benoit, *Polymers and Neutron Scattering*, Clarendon, Oxford, 1994 
    20052010 
    20062011 
     
    20472052REFERENCE 
    20482053 
    2049 S. Alexandru Rautu, Private Communication. 
     2054S Alexandru Rautu, Private Communication. 
    20502055 
    20512056 
     
    21432148REFERENCE 
    21442149 
    2145 L. A. Feigin and D. I. Svergun. *Structure Analysis by Small-Angle X-Ray and Neutron Scattering*, Plenum, 
     2150L A Feigin and D I Svergun. *Structure Analysis by Small-Angle X-Ray and Neutron Scattering*, Plenum, 
    21462151New York, 1987. 
    21472152 
     
    22072212REFERENCE 
    22082213 
    2209 M. Kotlarchyk, S.-H. Chen, *J. Chem. Phys.*, 79 (1983) 2461 
    2210  
    2211 S. J. Berr, *Phys. Chem.*, 91 (1987) 4760 
     2214M Kotlarchyk, S H Chen, *J. Chem. Phys.*, 79 (1983) 2461 
     2215 
     2216S J Berr, *Phys. Chem.*, 91 (1987) 4760 
    22122217 
    22132218 
     
    22722277REFERENCE 
    22732278 
    2274 R. K. Heenan, Private communication 
     2279R K Heenan, Private communication 
    22752280 
    22762281 
     
    23472352REFERENCE 
    23482353 
    2349 L. A. Feigin and D. I. Svergun, *Structure Analysis by Small-Angle X-Ray and Neutron Scattering*, Plenum, 
     2354L A Feigin and D I Svergun, *Structure Analysis by Small-Angle X-Ray and Neutron Scattering*, Plenum, 
    23502355New York, 1987. 
    23512356 
     
    23972402REFERENCE 
    23982403 
    2399 F. Nallet, R. Laversanne, and D. Roux, J. Phys. II France, 3, (1993) 487-502 
     2404F Nallet, R Laversanne, and D Roux, J. Phys. II France, 3, (1993) 487-502 
    24002405 
    24012406also in J. Phys. Chem. B, 105, (2001) 11081-11088 
     
    24512456REFERENCE 
    24522457 
    2453 F. Nallet, R. Laversanne, and D. Roux, J. Phys. II France, 3, (1993) 487-502 
     2458F Nallet, R Laversanne, and D Roux, J. Phys. II France, 3, (1993) 487-502 
    24542459 
    24552460also in J. Phys. Chem. B, 105, (2001) 11081-11088 
    24562461 
    2457 *2014/04/17 - Description reviewed by S. King and P. Butler.* 
     2462*2014/04/17 - Description reviewed by S King and P Butler.* 
    24582463 
    24592464 
     
    25182523REFERENCE 
    25192524 
    2520 F. Nallet, R. Laversanne, and D. Roux, J. Phys. II France, 3, (1993) 487-502 
     2525F Nallet, R Laversanne, and D Roux, J. Phys. II France, 3, (1993) 487-502 
    25212526 
    25222527also in J. Phys. Chem. B, 105, (2001) 11081-11088 
     
    25902595REFERENCE 
    25912596 
    2592 F. Nallet, R. Laversanne, and D. Roux, J. Phys. II France, 3, (1993) 487-502 
     2597F Nallet, R Laversanne, and D Roux, J. Phys. II France, 3, (1993) 487-502 
    25932598 
    25942599also in J. Phys. Chem. B, 105, (2001) 11081-11088 
     
    26512656REFERENCE 
    26522657 
    2653 M. Bergstrom, J. S. Pedersen, P. Schurtenberger, S. U. Egelhaaf, *J. Phys. Chem. B*, 103 (1999) 9888-9897 
     2658M Bergstrom, J S Pedersen, P Schurtenberger, S U Egelhaaf, *J. Phys. Chem. B*, 103 (1999) 9888-9897 
    26542659 
    26552660 
     
    30043009REFERENCE 
    30053010 
    3006 P. Mittelbach and G. Porod, *Acta Physica Austriaca*, 14 (1961) 185-211 
     3011P Mittelbach and G Porod, *Acta Physica Austriaca*, 14 (1961) 185-211 
    30073012Equations (1), (13-14). (in German) 
    30083013 
     
    31123117REFERENCE 
    31133118 
    3114 P. Mittelbach and G. Porod, *Acta Physica Austriaca*, 14 (1961) 185-211 
     3119P Mittelbach and G Porod, *Acta Physica Austriaca*, 14 (1961) 185-211 
    31153120Equations (1), (13-14). (in German) 
    31163121 
     
    31263131**2.2.1. Debye (Gaussian Coil Model)** 
    31273132 
    3128 The Debye model is a form factor for a linear polymer chain. In addition 
    3129 to the radius of gyration, Rg, a scale factor "scale", and a constant 
    3130 background term are included in the calculation. 
     3133The Debye model is a form factor for a linear polymer chain. In addition to the radius of gyration, *Rg*, a scale factor 
     3134*scale*, and a constant background term are included in the calculation. **NB: No size polydispersity is included in** 
     3135**this model, use the** Poly_GaussCoil_ **Model instead** 
    31313136 
    31323137.. image:: img/image172.PNG 
    31333138 
    3134 For 2D plot, the wave transfer is defined as 
     3139For 2D data: The 2D scattering intensity is calculated in the same way as 1D, where the *q* vector is defined as 
    31353140 
    31363141.. image:: img/image040.GIF 
     
    31503155REFERENCE 
    31513156 
    3152 Roe, R.-J., "Methods of X-Ray and Neutron Scattering in 
    3153 Polymer Science", Oxford University Press, New York (2000). 
     3157R J Roe, *Methods of X-Ray and Neutron Scattering in Polymer Science*, Oxford University Press, New York (2000) 
    31543158 
    31553159 
     
    31593163**2.2.2. BroadPeakModel** 
    31603164 
    3161 Calculate an empirical functional form for SANS data characterized by a 
    3162 broad scattering peak. Many SANS spectra are characterized by a broad 
    3163 peak even though they are from amorphous soft materials. The d-spacing 
    3164 corresponding to the broad peak is a characteristic distance between the 
    3165 scattering inhomogeneities (such as in lamellar, cylindrical, or 
    3166 spherical morphologies or for bicontinuous structures). 
     3165This model calculates an empirical functional form for SANS data characterized by a broad scattering peak. Many SANS 
     3166spectra are characterized by a broad peak even though they are from amorphous soft materials. For example, soft systems 
     3167that show a SANS peak include copolymers, polyelectrolytes, multiphase systems, layered structures, etc. 
     3168 
     3169The d-spacing corresponding to the broad peak is a characteristic distance between the scattering inhomogeneities (such 
     3170as in lamellar, cylindrical, or spherical morphologies, or for bicontinuous structures). 
    31673171 
    31683172The returned value is scaled to units of |cm^-1|, absolute scale. 
    31693173 
    3170 The scattering intensity *I(q)* is calculated by:  
     3174*2.2.2.1. Definition* 
     3175 
     3176The scattering intensity *I(q)* is calculated as 
    31713177 
    31723178.. image:: img/image174.JPG 
    31733179 
    3174 Here the peak position is related to the d-spacing as Q0 = 2pi/d0. Soft 
    3175 systems that show a SANS peak include copolymers, polyelectrolytes, 
    3176 multiphase systems, layered structures, etc. 
    3177  
    3178 For 2D plot, the wave transfer is defined as 
     3180Here the peak position is related to the d-spacing as *Q0* = 2|pi| / *d0*. 
     3181 
     3182For 2D data: The 2D scattering intensity is calculated in the same way as 1D, where the *q* vector is defined as 
    31793183 
    31803184.. image:: img/image040.GIF 
    31813185 
    3182 ===============  ========  ============= 
    3183 Parameter name   Units     Default value 
    3184 ===============  ========  ============= 
    3185 scale_l    (=C)  None      10 
    3186 scale_p    (=A)  None      1e-05 
    3187 length_l   (=x)  |Ang|     50 
    3188 q_peak    (=Q0)  |Ang^-1|  0.1 
    3189 exponent_p (=n)  None      2 
    3190 exponent_l (=m)  None      3 
    3191 Background (=B)  |cm^-1|   0.1 
    3192 ===============  ========  ============= 
     3186==================  ========  ============= 
     3187Parameter name      Units     Default value 
     3188==================  ========  ============= 
     3189scale_l    (=C)     None      10 
     3190scale_p    (=A)     None      1e-05 
     3191length_l (= |xi| )  |Ang|     50 
     3192q_peak    (=Q0)     |Ang^-1|  0.1 
     3193exponent_p (=n)     None      2 
     3194exponent_l (=m)     None      3 
     3195Background (=B)     |cm^-1|   0.1 
     3196==================  ========  ============= 
    31933197 
    31943198.. image:: img/image175.JPG 
     
    32003204None. 
    32013205 
    3202 *2013/09/09 - Description reviewed by King, S. and Parker, P.* 
     3206*2013/09/09 - Description reviewed by King, S and Parker, P.* 
    32033207 
    32043208 
     
    32083212**2.2.3. CorrLength (Correlation Length Model)** 
    32093213 
    3210 Calculate an empirical functional form for SANS data characterized by a 
    3211 low-Q signal and a high-Q signal 
     3214Calculates an empirical functional form for SANS data characterized by a low-Q signal and a high-Q signal. 
    32123215 
    32133216The returned value is scaled to units of |cm^-1|, absolute scale. 
    32143217 
    3215 The scattering intensity *I(q)* is calculated by:  
     3218*2.2.3. Definition* 
     3219 
     3220The scattering intensity *I(q)* is calculated as 
    32163221 
    32173222.. image:: img/image176.JPG 
    32183223 
    3219 The first term describes Porod scattering from clusters (exponent = n) 
    3220 and the second term is a Lorentzian function describing scattering from 
    3221 polymer chains (exponent = m). This second term characterizes the 
    3222 polymer/solvent interactions and therefore the thermodynamics. The two 
    3223 multiplicative factors A and C, the incoherent background B and the two 
    3224 exponents n and m are used as fitting parameters. The final parameter 
    3225 (xi) is a correlation length for the polymer chains. Note that when m = 
    3226 2, this functional form becomes the familiar Lorentzian function.  
    3227  
    3228 For 2D plot, the wave transfer is defined as 
     3224The first term describes Porod scattering from clusters (exponent = n) and the second term is a Lorentzian function 
     3225describing scattering from polymer chains (exponent = *m*). This second term characterizes the polymer/solvent 
     3226interactions and therefore the thermodynamics. The two multiplicative factors *A* and *C*, the incoherent 
     3227background *B* and the two exponents *n* and *m* are used as fitting parameters. The final parameter |xi| is a 
     3228correlation length for the polymer chains. Note that when *m*\ =2 this functional form becomes the familiar Lorentzian 
     3229function.  
     3230 
     3231For 2D data: The 2D scattering intensity is calculated in the same way as 1D, where the *q* vector is defined as 
    32293232 
    32303233.. image:: img/image040.GIF 
    32313234 
    3232 ===============  ========  ============= 
    3233 Parameter name   Units     Default value 
    3234 ===============  ========  ============= 
    3235 scale_l    (=C)  None      10 
    3236 scale_p    (=A)  None      1e-06 
    3237 length_l   (=x)  |Ang|     50 
    3238 exponent_p (=n)  None      2 
    3239 exponent_l (=m)  None      3 
    3240 Background (=B)  |cm^-1|   0.1 
    3241 ===============  ========  ============= 
     3235====================  ========  ============= 
     3236Parameter name        Units     Default value 
     3237====================  ========  ============= 
     3238scale_l    (=C)       None      10 
     3239scale_p    (=A)       None      1e-06 
     3240length_l   (= |xi| )  |Ang|     50 
     3241exponent_p (=n)       None      2 
     3242exponent_l (=m)       None      3 
     3243Background (=B)       |cm^-1|   0.1 
     3244====================  ========  ============= 
    32423245 
    32433246.. image:: img/image177.JPG 
     
    32473250REFERENCE 
    32483251 
    3249 B. Hammouda, D.L. Ho and S.R. Kline, Insight into Clustering in 
    3250 Poly(ethylene oxide) Solutions, Macromolecules 37, 6932-6937 (2004). 
    3251  
    3252 *2013/09/09 - Description reviewed by King, S. and Parker, P.* 
     3252B Hammouda, D L Ho and S R Kline, *Insight into Clustering in Poly(ethylene oxide) Solutions*, *Macromolecules*, 37 
     3253(2004) 6932-6937 
     3254 
     3255*2013/09/09 - Description reviewed by King, S and Parker, P.* 
    32533256 
    32543257 
     
    32583261**2.2.4. Lorentz (Ornstein-Zernicke Model)** 
    32593262 
    3260 The Ornstein-Zernicke model is defined by: 
     3263*2.2.4.1. Definition* 
     3264 
     3265The Ornstein-Zernicke model is defined by 
    32613266 
    32623267.. image:: img/image178.PNG 
    32633268 
    3264 The parameter L is referred to as the screening length. 
    3265  
    3266 For 2D plot, the wave transfer is defined as 
     3269The parameter *L* is the screening length. 
     3270 
     3271For 2D data: The 2D scattering intensity is calculated in the same way as 1D, where the *q* vector is defined as 
    32673272 
    32683273.. image:: img/image040.GIF 
     
    32783283.. image:: img/image179.JPG 
    32793284 
    3280 ** Figure. 1D plot using the default values (w/200 data point).** 
     3285* Figure. 1D plot using the default values (w/200 data point).* 
     3286 
     3287REFERENCE 
     3288 
     3289None. 
    32813290 
    32823291 
     
    32863295**2.2.5. DABModel (Debye-Anderson-Brumberger Model)** 
    32873296 
    3288 Calculates the scattering from a randomly distributed, two-phase system 
    3289 based on the Debye-Anderson-Brumberger (DAB) model for such systems. The 
    3290 two-phase system is characterized by a single length scale, the 
    3291 correlation length, which is a measure of the average spacing between 
    3292 regions of phase 1 and phase 2. The model also assumes smooth interfaces 
    3293 between the phases and hence exhibits Porod behavior (I ~ Q-4) at large 
    3294 Q (Q\*correlation length >> 1). 
     3297Calculates the scattering from a randomly distributed, two-phase system based on the Debye-Anderson-Brumberger (DAB) 
     3298model for such systems. The two-phase system is characterized by a single length scale, the correlation length, which 
     3299is a measure of the average spacing between regions of phase 1 and phase 2. **The model also assumes smooth interfaces** 
     3300**between the phases** and hence exhibits Porod behavior (I ~ *q*\ :sup:`-4`) at large *q* (*QL* >> 1). 
     3301 
     3302The DAB model is ostensibly a development of the earlier Debye-Bueche model. 
     3303 
     3304*2.2.5.1. Definition* 
    32953305 
    32963306.. image:: img/image180.PNG 
    32973307 
    3298 The parameter L is referred to as the correlation length. 
    3299  
    3300 For 2D plot, the wave transfer is defined as 
     3308The parameter *L* is the correlation length. 
     3309 
     3310For 2D data: The 2D scattering intensity is calculated in the same way as 1D, where the *q* vector is defined as 
    33013311 
    33023312.. image:: img/image040.GIF 
     
    33123322.. image:: img/image181.JPG 
    33133323 
    3314 ** Figure. 1D plot using the default values (w/200 data point).** 
    3315  
    3316 REFERENCE 
    3317  
    3318 Debye, Anderson, Brumberger, "Scattering by an Inhomogeneous Solid. II. 
    3319 The Correlation Function and its Application", J. Appl. Phys. 28 (6), 
    3320 679 (1957). 
    3321  
    3322 Debye, Bueche, "Scattering by an Inhomogeneous Solid", J. Appl. Phys. 
    3323 20, 518 (1949). 
    3324  
    3325 *2013/09/09 - Description reviewed by King, S. and Parker, P.* 
     3324* Figure. 1D plot using the default values (w/200 data point).* 
     3325 
     3326REFERENCE 
     3327 
     3328P Debye, H R Anderson, H Brumberger, *Scattering by an Inhomogeneous Solid. II. The Correlation Function* 
     3329*and its Application*, *J. Appl. Phys.*, 28(6) (1957) 679 
     3330 
     3331P Debye, A M Bueche, *Scattering by an Inhomogeneous Solid*, *J. Appl. Phys.*, 20 (1949) 518 
     3332 
     3333*2013/09/09 - Description reviewed by King, S and Parker, P.* 
    33263334 
    33273335 
     
    33313339**2.2.6. AbsolutePower_Law** 
    33323340 
    3333 This model describes a power law with background. 
     3341This model describes a simple power law with background. 
    33343342 
    33353343.. image:: img/image182.PNG 
    33363344 
    3337 Note the minus sign in front of the exponent. 
     3345Note the minus sign in front of the exponent. The parameter *m* should therefore be entered as a **positive** number. 
    33383346 
    33393347==============  ========  ============= 
     
    33493357*Figure. 1D plot using the default values (w/200 data point).* 
    33503358 
    3351  
    3352  
    3353 .. _Teubner Strey: 
    3354  
    3355 **2.2.7. Teubner Strey (Model)** 
    3356  
    3357 This function calculates the scattered intensity of a two-component 
    3358 system using the Teubner-Strey model. 
     3359REFERENCE 
     3360 
     3361None. 
     3362 
     3363 
     3364 
     3365.. _TeubnerStrey: 
     3366 
     3367**2.2.7. TeubnerStrey (Model)** 
     3368 
     3369This function calculates the scattered intensity of a two-component system using the Teubner-Strey model. Unlike the 
     3370DABModel_ this function generates a peak. 
     3371 
     3372*2.2.7.1. Definition* 
    33593373 
    33603374.. image:: img/image184.PNG 
    33613375 
    3362 For 2D plot, the wave transfer is defined as 
     3376For 2D data: The 2D scattering intensity is calculated in the same way as 1D, where the *q* vector is defined as 
    33633377 
    33643378.. image:: img/image040.GIF 
     
    33793393REFERENCE 
    33803394 
    3381 Teubner, M; Strey, R. J. Chem. Phys., 87, 3195 (1987). 
    3382  
    3383 Schubert, K-V., Strey, R., Kline, S. R. and E. W. Kaler, J. Chem. Phys., 
    3384 101, 5343 (1994). 
     3395M Teubner, R Strey, *J. Chem. Phys.*, 87 (1987) 3195 
     3396 
     3397K V Schubert, R Strey, S R Kline and E W Kaler, *J. Chem. Phys.*, 101 (1994) 5343 
    33853398 
    33863399 
     
    33903403**2.2.8. FractalModel** 
    33913404 
    3392 Calculates the scattering from fractal-like aggregates built from 
    3393 spherical building blocks following the Texiera reference. The value 
    3394 returned is in cm-1. 
     3405Calculates the scattering from fractal-like aggregates built from spherical building blocks following the Texiera 
     3406reference. 
     3407 
     3408The value returned is in |cm^-1|\ . 
     3409 
     3410*2.2.8.1. Definition* 
    33953411 
    33963412.. image:: img/image186.PNG 
    33973413 
    3398 The scale parameter is the volume fraction of the building blocks, R0 is 
    3399 the radius of the building block, Df is the fractal dimension, Ο is the 
    3400 correlation length, *Ïᅵsolvent* is the scattering length density of the 
    3401 solvent, and *Ïᅵblock* is the scattering length density of the building 
    3402 blocks. 
    3403  
    3404 **The polydispersion in radius is provided.** 
    3405  
    3406 For 2D plot, the wave transfer is defined as 
     3414The *scale* parameter is the volume fraction of the building blocks, *R0* is the radius of the building block, *Df* is 
     3415the fractal dimension, |xi| is the correlation length, |rho|\ *solvent* is the scattering length density of the 
     3416solvent, and |rho|\ *block* is the scattering length density of the building blocks. 
     3417 
     3418**Polydispersity on the radius is provided for.** 
     3419 
     3420For 2D data: The 2D scattering intensity is calculated in the same way as 1D, where the *q* vector is defined as 
    34073421 
    34083422.. image:: img/image040.GIF 
     
    34263440REFERENCE 
    34273441 
    3428 J. Teixeira, (1988) J. Appl. Cryst., vol. 21, p781-785 
     3442J Teixeira, *J. Appl. Cryst.*, 21 (1988) 781-785 
    34293443 
    34303444 
     
    34343448**2.2.9. MassFractalModel** 
    34353449 
    3436 Calculates the scattering from fractal-like aggregates based on the 
    3437 Mildner reference (below).  
     3450Calculates the scattering from fractal-like aggregates based on the Mildner reference. 
     3451 
     3452*2.2.9.1. Definition* 
    34383453 
    34393454.. image:: img/mass_fractal_eq1.JPG 
    34403455 
    3441 The R is the radius of the building block, Dm is the mass fractal 
    3442 dimension, Ο is the correlation (or cutt-off)  length, *Ïᅵsolvent* is the 
    3443 scattering length density of the solvent, and *Ïᅵparticle* is the 
    3444 scattering length density of particles. 
    3445  
    3446 Note:  The mass fractal dimension is valid for 1<mass_dim<6. 
     3456where *R* is the radius of the building block, *Dm* is the **mass** fractal dimension, |zeta| is the cut-off length, 
     3457|rho|\ *solvent* is the scattering length density of the solvent, and |rho|\ *particle* is the scattering length 
     3458density of particles. 
     3459 
     3460Note:  The mass fractal dimension *Dm* is only valid if 1 < mass_dim < 6. It is also only valid over a limited 
     3461*q* range (see the reference for details). 
    34473462 
    34483463==============  ========  ============= 
     
    34583473.. image:: img/mass_fractal_fig1.JPG 
    34593474 
    3460 *Figure. 1D plot* 
    3461  
    3462 REFERENCE 
    3463  
    3464 D. Mildner, and P. Hall,  J. Phys. D.: Appl. Phys.,  19, 1535-1545  
    3465 (1986), Equation(9). 
    3466  
    3467 *2013/09/09 - Description reviewed by King, S. and Parker, P.* 
     3475*Figure. 1D plot using default values.* 
     3476 
     3477REFERENCE 
     3478 
     3479D Mildner and P Hall, *J. Phys. D: Appl. Phys.*,  19 (1986) 1535-1545 
     3480Equation(9) 
     3481 
     3482*2013/09/09 - Description reviewed by King, S and Parker, P.* 
    34683483 
    34693484 
     
    34733488**2.2.10. SurfaceFractalModel** 
    34743489 
    3475 Calculates the scattering  based on the Mildner reference (below).  
     3490Calculates the scattering from fractal-like aggregates based on the Mildner reference. 
     3491 
     3492*2.2.10.1. Definition* 
    34763493 
    34773494.. image:: img/surface_fractal_eq1.GIF  
    34783495 
    3479 The R is the radius of the building block, Ds is the surface fractal 
    3480 dimension, Ο is the correlation (or cutt-off)  length, *Ïᅵsolvent* is the 
    3481 scattering length density of the solvent, and *Ïᅵparticle* is the 
    3482 scattering length density of particles. 
    3483  
    3484 Â Note:  The surface fractal dimension is valid for 1<surface_dim<3. 
    3485 Â Also it is valid in a limited q range (see the reference for details). 
     3496where *R* is the radius of the building block, *Ds* is the **surface** fractal dimension, |zeta| is the cut-off length, 
     3497|rho|\ *solvent* is the scattering length density of the solvent, and |rho|\ *particle* is the scattering length 
     3498density of particles. 
     3499 
     3500Note:  The surface fractal dimension *Ds* is only valid if 1 < surface_dim < 3. It is also only valid over a limited 
     3501*q* range (see the reference for details). 
    34863502 
    34873503==============  ========  ============= 
     
    34973513.. image:: img/surface_fractal_fig1.JPG 
    34983514 
    3499 *Figure. 1D plot* 
    3500  
    3501 REFERENCE 
    3502  
    3503 D. Mildner, and P. Hall,  J. Phys. D.: Appl. Phys.,  19, 1535-1545  
    3504 (1986), Equation(13). 
     3515*Figure. 1D plot using default values.* 
     3516 
     3517REFERENCE 
     3518 
     3519D Mildner and P Hall, *J. Phys. D: Appl. Phys.*,  19 (1986) 1535-1545 
     3520Equation(13) 
    35053521 
    35063522 
     
    35103526**2.2.11. MassSurfaceFractal (Model)** 
    35113527 
    3512 A number of natural and commercial processes form high-surface area 
    3513 materials as a result of the vapour-phase aggregation of primary 
    3514 particles. Examples of such materials include soots, aerosols, and 
    3515 fume or pyrogenic silicas. These are all characterised by cluster mass 
    3516 distributions (sometimes also cluster size distributions) and internal 
    3517 surfaces that are fractal in nature.   The scattering from such 
    3518 materials displays two distinct breaks in log-log representation, 
    3519 corresponding to the radius-of-gyration of the primary particles, rg, 
    3520 and the radius-of-gyration of the clusters (aggregates), Rg. Between 
    3521 these boundaries the scattering follows a power law related to the mass 
    3522 fractal dimension, Dm, whilst above the high-Q boundary the scattering 
    3523 follows a power law related to the surface fractal dimension of the 
    3524 primary particles, Ds. 
    3525  
    3526 The scattered intensity *I(q)* is then calculated using a modified 
    3527 Ornstein-Zernicke equation: 
     3528A number of natural and commercial processes form high-surface area materials as a result of the vapour-phase 
     3529aggregation of primary particles. Examples of such materials include soots, aerosols, and fume or pyrogenic silicas. 
     3530These are all characterised by cluster mass distributions (sometimes also cluster size distributions) and internal 
     3531surfaces that are fractal in nature. The scattering from such materials displays two distinct breaks in log-log 
     3532representation, corresponding to the radius-of-gyration of the primary particles, *rg*, and the radius-of-gyration of 
     3533the clusters (aggregates), *Rg*. Between these boundaries the scattering follows a power law related to the mass 
     3534fractal dimension, *Dm*, whilst above the high-Q boundary the scattering follows a power law related to the surface 
     3535fractal dimension of the primary particles, *Ds*. 
     3536 
     3537*2.2.11.1. Definition* 
     3538 
     3539The scattered intensity *I(q)* is  calculated using a modified Ornstein-Zernicke equation 
    35283540 
    35293541.. image:: img/masssurface_fractal_eq1.JPG  
    35303542 
    3531 The Rg is for the cluster, rg is for the primary, Ds is the surface 
    3532 fractal dimension, Dm is the mass fractal dimension, *Ïᅵsolvent* is the 
    3533 scattering length density of the solvent, and *Ïᅵp* is the scattering 
    3534 length density of particles. 
    3535  
    3536 Â Note:  The surface and mass fractal dimensions are valid for 
    3537 0<surface_dim<6, 0<mass_dim<6, and (surface_mass+mass_dim)<6.  
     3543where *Rg* is the size of the cluster, *rg* is the size of the primary particle, *Ds* is the surface fractal dimension, 
     3544*Dm* is the mass fractal dimension, |rho|\ *solvent* is the scattering length density of the solvent, and |rho|\ *p* is 
     3545the scattering length density of particles. 
     3546 
     3547Note:  The surface (*Ds*) and mass (*Dm*) fractal dimensions are only valid if 0 < *surface_dim* < 6, 
     35480 < *mass_dim* < 6, and (*surface_dim*+*mass_dim*) < 6.  
    35383549 
    35393550==============  ========  ============= 
     
    35503561.. image:: img/masssurface_fractal_fig1.JPG 
    35513562 
    3552 *Figure. 1D plot* 
    3553  
    3554 REFERENCE 
    3555  
    3556 P. Schmidt, J Appl. Cryst., 24, 414-435  (1991), Equation(19). 
    3557  
    3558 Hurd, Schaefer, Martin, Phys. Rev. A, 35, 2361-2364 (1987), Equation(2). 
     3563*Figure. 1D plot using default values.* 
     3564 
     3565REFERENCE 
     3566 
     3567P Schmidt, *J Appl. Cryst.*, 24 (1991) 414-435 
     3568Equation(19) 
     3569 
     3570A J Hurd, D W Schaefer, J E Martin, *Phys. Rev. A*, 35 (1987) 2361-2364 
     3571Equation(2) 
    35593572 
    35603573 
     
    35643577**2.2.12. FractalCoreShell (Model)** 
    35653578 
    3566 Calculates the scattering from a fractal structure with a primary 
    3567 building block of core-shell spheres. 
     3579Calculates the scattering from a fractal structure with a primary building block of core-shell spheres, as opposed to 
     3580just homogeneous spheres in the FractalModel_. This model could find use for aggregates of coated particles, or 
     3581aggregates of vesicles. 
     3582 
     3583The returned value is scaled to units of |cm^-1|, absolute scale. 
     3584 
     3585*2.2.12.1. Definition* 
    35683586 
    35693587.. image:: img/fractcore_eq1.GIF 
    35703588 
    3571 The formfactor P(q) is `CoreShellModel <#CoreShellModel>`__ with bkg 
    3572 = 0, 
     3589The form factor *P(q)* is that from CoreShellModel_ with *bkg* = 0 
    35733590 
    35743591.. image:: img/image013.PNG 
    35753592 
    3576 while the fractal structure factor S(q); 
     3593while the fractal structure factor S(q) is 
    35773594 
    35783595.. image:: img/fractcore_eq3.gif 
    35793596 
    3580 where Df = frac_dim, Ο = cor_length, rc = (core) radius, and scale 
    3581 = volfraction. 
    3582  
    3583 The fractal structure is as documented in the fractal model. This model 
    3584 could find use for aggregates of coated particles, or aggregates of 
    3585 vesicles. The polydispersity computation of radius and thickness is 
    3586 provided. 
    3587  
    3588 The returned value is scaled to units of |cm^-1|, absolute scale. 
    3589  
    3590 See each of these individual models for full documentation.  
    3591  
    3592 For 2D plot, the wave transfer is defined as 
     3597where *Df* = frac_dim, |xi| = cor_length, *rc* = (core) radius, and *scale* = volume fraction. 
     3598 
     3599The fractal structure is as documented in the FractalModel_. Polydispersity of radius and thickness is provided for. 
     3600 
     3601For 2D data: The 2D scattering intensity is calculated in the same way as 1D, where the *q* vector is defined as 
    35933602 
    35943603.. image:: img/image040.GIF 
     
    36143623REFERENCE 
    36153624 
    3616 See the PolyCore and Fractal documentation.\ 
     3625See the CoreShellModel_ and FractalModel_ descriptions. 
    36173626 
    36183627 
     
    36223631**2.2.13. GaussLorentzGel(Model)** 
    36233632 
    3624 Calculates the scattering from a gel structure, typically a physical 
    3625 network. It is modeled as a sum of a low-q exponential decay plus a 
    3626 lorentzian at higher q-values. It is generally applicable to gel 
    3627 structures. 
     3633Calculates the scattering from a gel structure, but typically a physical rather than chemical network. It is modeled as 
     3634a sum of a low-*q* exponential decay plus a lorentzian at higher *q*-values. 
    36283635 
    36293636The returned value is scaled to units of |cm^-1|, absolute scale. 
    36303637 
    3631 The scattering intensity *I(q)* is calculated as (eqn 5 from the 
    3632 reference): 
     3638*2.2.13.1. Definition* 
     3639 
     3640The scattering intensity *I(q)* is calculated as (eqn 5 from the reference) 
    36333641 
    36343642.. image:: img/image189.JPG 
    36353643 
    3636 Uppercase Zeta is the static correlations in the gel, which can be 
    3637 attributed to the "frozen-in" crosslinks of some gels. Lowercase zeta is 
    3638 the dynamic correlation length, which can be attributed to the 
    3639 fluctuating polymer chain between crosslinks. IG(0) and IL(0) are the 
    3640 scaling factors for each of these structures. Your physical system may 
    3641 be different, so think about the interpretation of these parameters. 
    3642  
    3643 Note that the peaked structure at higher q values (from Figure 2 of the 
    3644 reference below) is not reproduced by the model. Peaks can be introduced 
    3645 into the model by summing this model with the PeakGauss Model function. 
    3646  
    3647 For 2D plot, the wave transfer is defined as 
     3644|bigzeta| is the length scale of the static correlations in the gel, which can be attributed to the "frozen-in" 
     3645crosslinks. |xi| is the dynamic correlation length, which can be attributed to the fluctuating polymer chains between 
     3646crosslinks. *I*\ :sub:`G`\ *(0)* and *I*\ :sub:`L`\ *(0)* are the scaling factors for each of these structures. **Think carefully about how** 
     3647**these map to your particular system!** 
     3648 
     3649NB: The peaked structure at higher *q* values (Figure 2 from the reference) is not reproduced by the model. Peaks can 
     3650be introduced into the model by summing this model with the PeakGaussModel_ function. 
     3651 
     3652For 2D data: The 2D scattering intensity is calculated in the same way as 1D, where the *q* vector is defined as 
    36483653 
    36493654.. image:: img/image040.GIF 
     
    36653670REFERENCE 
    36663671 
    3667 G. Evmenenko, E. Theunissen, K. Mortensen, H. Reynaers, Polymer 42 
    3668 (2001) 2907-2913. 
     3672G Evmenenko, E Theunissen, K Mortensen, H Reynaers, *Polymer*, 42 (2001) 2907-2913 
    36693673 
    36703674 
     
    36743678**2.2.14. BEPolyelectrolyte (Model)** 
    36753679 
    3676 Calculates the structure factor of a polyelectrolyte solution with the 
    3677 RPA expression derived by Borue and Erukhimovich. The value returned is 
    3678 in cm-1. 
     3680Calculates the structure factor of a polyelectrolyte solution with the RPA expression derived by Borue and Erukhimovich. 
     3681 
     3682The value returned is in |cm^-1|. 
     3683 
     3684*2.2.14.1. Definition* 
    36793685 
    36803686.. image:: img/image191.PNG 
    36813687 
    3682 K is a contrast factor of the polymer, Lb is the Bjerrum length, h is 
    3683 the virial parameter, b is the monomer length, Cs is the concentration 
    3684 of monovalent salt, α is the ionization degree, Ca is the polymer molar 
    3685 concentration, and background is the incoherent background. 
    3686  
    3687 For 2D plot, the wave transfer is defined as 
     3688where *K* is the contrast factor for the polymer, *Lb* is the Bjerrum length, *h* is the virial parameter, *b* is the 
     3689monomer length, *Cs* is the concentration of monovalent salt, |alpha| is the ionization degree, *Ca* is the polymer 
     3690molar concentration, and *background* is the incoherent background. 
     3691 
     3692For 2D data: The 2D scattering intensity is calculated in the same way as 1D, where the *q* vector is defined as 
    36883693 
    36893694.. image:: img/image040.GIF 
     
    37063711REFERENCE 
    37073712 
    3708 Borue, V. Y., Erukhimovich, I. Y. Macromolecules 21, 3240 (1988). 
    3709  
    3710 Joanny, J.-F., Leibler, L. Journal de Physique 51, 545 (1990). 
    3711  
    3712 Moussaid, A., Schosseler, F., Munch, J.-P., Candau, S. J. Journal de 
    3713 Physique II France 3, 573 (1993). 
    3714  
    3715 Raphaël, E., Joanny, J.-F., Europhysics Letters 11, 179 (1990). 
     3713V Y Borue, I Y Erukhimovich, *Macromolecules*, 21 (1988) 3240 
     3714 
     3715J F Joanny, L Leibler, *Journal de Physique*, 51 (1990) 545 
     3716 
     3717A Moussaid, F Schosseler, J P Munch, S Candau, *J. Journal de Physique II France*, 3 (1993) 573 
     3718 
     3719E Raphael, J F Joanny, *Europhysics Letters*, 11 (1990) 179 
    37163720 
    37173721 
     
    37213725**2.2.15. Guinier (Model)** 
    37223726 
    3723 A Guinier analysis is done by linearizing the data at low q by plotting 
    3724 it as log(I) versus Q2. The Guinier radius Rg can be obtained by fitting 
    3725 the following model: 
     3727This model fits the Guinier function 
    37263728 
    37273729.. image:: img/image192.PNG 
    37283730 
    3729 For 2D plot, the wave transfer is defined as 
     3731to the data directly without any need for linearisation (*cf*. Ln *I(q)* vs *q*\ :sup:`2`). 
     3732 
     3733For 2D data: The 2D scattering intensity is calculated in the same way as 1D, where the *q* vector is defined as 
    37303734 
    37313735.. image:: img/image040.GIF 
     
    37383742==============  ========  ============= 
    37393743 
     3744REFERENCE 
     3745 
     3746A Guinier and G Fournet, *Small-Angle Scattering of X-Rays*, John Wiley & Sons, New York (1955) 
     3747 
    37403748 
    37413749 
     
    37443752**2.2.16. GuinierPorod (Model)** 
    37453753 
    3746 Calculates the scattering for a generalized Guinier/power law object. 
    3747 This is an empirical model that can be used to determine the size and 
    3748 dimensionality of scattering objects. 
    3749  
    3750 The returned value is P(Q) as written in equation (1), plus the 
    3751 incoherent background term. The result is in the units of |cm^-1|, 
    3752 absolute scale. 
    3753  
    3754 A Guinier-Porod empirical model can be used to fit SAS data from 
    3755 asymmetric objects such as rods or platelets. It also applies to 
    3756 intermediate shapes between spheres and rod or between rods and 
    3757 platelets. The following functional form is used:  
    3758  
    3759 .. image:: img/image193.JPG   (1) 
    3760  
    3761 This is based on the generalized Guinier law for such elongated objects 
    3762 [2]. For 3D globular objects (such as spheres), s = 0 and one recovers 
    3763 the standard Guinier formula. For 2D symmetry (such as for rods) s = 1 
    3764 and for 1D symmetry (such as for lamellae or platelets) s = 2. A 
    3765 dimensionality parameter 3-s is defined, and is 3 for spherical objects, 
    3766 2 for rods, and 1 for plates. 
    3767  
    3768 Enforcing the continuity of the Guinier and Porod functions and their 
    3769 derivatives yields:  
     3754Calculates the scattering for a generalized Guinier/power law object. This is an empirical model that can be used to 
     3755determine the size and dimensionality of scattering objects, including asymmetric objects such as rods or platelets, and 
     3756shapes intermediate between spheres and rods or between rods and platelets. 
     3757 
     3758The result is in the units of |cm^-1|, absolute scale. 
     3759 
     3760*2.2.16.1 Definition* 
     3761 
     3762The following functional form is used 
     3763 
     3764.. image:: img/image193.JPG 
     3765 
     3766This is based on the generalized Guinier law for such elongated objects (see the Glatter reference below). For 3D 
     3767globular objects (such as spheres), *s* = 0 and one recovers the standard Guinier_ formula. For 2D symmetry (such as 
     3768for rods) *s* = 1, and for 1D symmetry (such as for lamellae or platelets) *s* = 2. A dimensionality parameter (3-*s*) 
     3769is thus defined, and is 3 for spherical objects, 2 for rods, and 1 for plates. 
     3770 
     3771Enforcing the continuity of the Guinier and Porod functions and their derivatives yields 
    37703772 
    37713773.. image:: img/image194.JPG 
     
    37753777.. image:: img/image195.JPG 
    37763778 
    3777 Note that the radius of gyration for a sphere of radius R is given by Rg 
    3778 = R sqrt(3/5) , 
    3779  
    3780 Â that for the cross section of an randomly oriented cylinder of radius R 
    3781 is given by  Rg = R / sqrt(2). 
    3782  
    3783 The cross section of a randomly oriented lamella of thickness T is given 
    3784 by Rg = T / sqrt(12). 
    3785  
    3786 The intensity given by Eq. 1 is the calculated result, and is plotted 
    3787 below for the default parameter values. 
    3788  
    3789 REFERENCE 
    3790  
    3791 [1] Guinier, A.; Fournet, G. "Small-Angle Scattering of X-Rays", John 
    3792 Wiley and Sons, New York, (1955). 
    3793  
    3794 [2] Glatter, O.; Kratky, O., Small-Angle X-Ray Scattering, Academic 
    3795 Press (1982). Check out Chapter 4 on Data Treatment, pages 155-156.  
    3796  
    3797 For 2D plot, the wave transfer is defined as 
     3779Note that 
     3780 
     3781 the radius of gyration for a sphere of radius *R* is given by *Rg* = *R* sqrt(3/5) 
     3782 
     3783 the cross-sectional radius of gyration for a randomly oriented cylinder of radius *R* is given by *Rg* = *R* / sqrt(2) 
     3784 
     3785 the cross-sectional radius of gyration of a randomly oriented lamella of thickness *T* is given by *Rg* = *T* / sqrt(12) 
     3786 
     3787For 2D data: The 2D scattering intensity is calculated in the same way as 1D, where the *q* vector is defined as 
    37983788 
    37993789.. image:: img/image008.PNG 
     
    38133803*Figure. 1D plot using the default values (w/500 data points).* 
    38143804 
     3805REFERENCE 
     3806 
     3807A Guinier, G Fournet, *Small-Angle Scattering of X-Rays*, John Wiley and Sons, New York, (1955) 
     3808 
     3809O Glatter, O Kratky, *Small-Angle X-Ray Scattering*, Academic Press (1982) 
     3810Check out Chapter 4 on Data Treatment, pages 155-156. 
     3811 
    38153812 
    38163813 
     
    38303827The background term is added for data analysis. 
    38313828 
    3832 For 2D plot, the wave transfer is defined as 
     3829For 2D data: The 2D scattering intensity is calculated in the same way as 1D, where the *q* vector is defined as 
    38333830 
    38343831.. image:: img/image040.GIF 
     
    38603857None 
    38613858 
    3862 For 2D plot, the wave transfer is defined as 
     3859For 2D data: The 2D scattering intensity is calculated in the same way as 1D, where the *q* vector is defined as 
    38633860 
    38643861.. image:: img/image040.GIF 
     
    38963893None 
    38973894 
    3898 For 2D plot, the wave transfer is defined as 
     3895For 2D data: The 2D scattering intensity is calculated in the same way as 1D, where the *q* vector is defined as 
    38993896 
    39003897.. image:: img/image040.GIF 
     
    39403937The polydispersion in rg is provided. 
    39413938 
    3942 For 2D plot, the wave transfer is defined as 
     3939For 2D data: The 2D scattering intensity is calculated in the same way as 1D, where the *q* vector is defined as 
    39433940 
    39443941.. image:: img/image040.GIF 
     
    39463943TEST DATASET 
    39473944 
    3948 This example dataset is produced by running the Poly_GaussCoil, using 200 data points, *qmin* = 0.001 |Ang^-1|\ , 
     3945This example dataset is produced by running the Poly_GaussCoil, using 200 data points, *qmin* = 0.001 |Ang^-1| , 
    39493946qmax = 0.7 |Ang^-1| and the default values below. 
    39503947 
     
    39643961REFERENCE 
    39653962 
    3966 Glatter & Kratky - pg.404. 
    3967  
    3968 J.S. Higgins, and H.C. Benoit, Polymers and Neutron Scattering, Oxford 
    3969 Science Publications (1996). 
     3963Glatter & Kratky - p404 
     3964 
     3965J S Higgins, and H C Benoit, Polymers and Neutron Scattering, Oxford Science Publications (1996) 
    39703966 
    39713967 
     
    40384034REFERENCE 
    40394035 
    4040 Benoit, H., Comptes Rendus (1957). 245, 2244-2247. 
    4041  
    4042 Hammouda, B., SANS from Homogeneous Polymer Mixtures ­ A Unified 
    4043 Overview, Advances in Polym. Sci. (1993), 106, 87-133. 
    4044  
    4045 For 2D plot, the wave transfer is defined as 
     4036H Benoit, *Comptes Rendus*, 245 (1957) 2244-2247 
     4037 
     4038B Hammouda, *SANS from Homogeneous Polymer Mixtures ­ A Unified Overview*, *Advances in Polym. Sci.*, 106 (1993) 87-133 
     4039 
     4040For 2D data: The 2D scattering intensity is calculated in the same way as 1D, where the *q* vector is defined as 
    40464041 
    40474042.. image:: img/image040.GIF 
     
    40494044TEST DATASET 
    40504045 
    4051 This example dataset is produced, using 200 data points, qmin = 0.001 |Ang^-1|\ ,  qmax = 0.2 |Ang^-1|  and the 
     4046This example dataset is produced, using 200 data points, qmin = 0.001 |Ang^-1| ,  qmax = 0.2 |Ang^-1|  and the 
    40524047default values below. 
    40534048 
     
    41224117REFERENCE 
    41234118 
    4124 A.Z. Akcasu, R. Klein and B. Hammouda, Macromolecules 26, 4136 (1993) 
     4119A Z Akcasu, R Klein and B Hammouda, *Macromolecules*, 26 (1993) 4136 
    41254120 
    41264121Fitting parameters for Case0 Model 
     
    41804175The background term is added for data analysis. 
    41814176 
    4182 For 2D plot, the wave transfer is defined as 
     4177For 2D data: The 2D scattering intensity is calculated in the same way as 1D, where the *q* vector is defined as 
    41834178 
    41844179.. image:: img/image040.GIF 
     
    42264221Be sure to enter the power law exponents as positive values. 
    42274222 
    4228 For 2D plot, the wave transfer is defined as 
     4223For 2D data: The 2D scattering intensity is calculated in the same way as 1D, where the *q* vector is defined as 
    42294224 
    42304225.. image:: img/image040.GIF 
     
    42584253 
    42594254Otherwise, program incorporates the empirical multiple level unified 
    4260 Exponential/Power-law fit method developed by G. Beaucage. Four 
     4255Exponential/Power-law fit method developed by G Beaucage. Four 
    42614256functions are included so that One, Two, Three, or Four levels can be 
    42624257used. 
     
    42774272parameters. 
    42784273 
    4279 For 2D plot, the wave transfer is defined as 
     4274For 2D data: The 2D scattering intensity is calculated in the same way as 1D, where the *q* vector is defined as 
    42804275 
    42814276.. image:: img/image040.GIF 
     
    43044299REFERENCE 
    43054300 
    4306 G. Beaucage (1995).  J. Appl. Cryst., vol. 28, p717-728. 
    4307  
    4308 G. Beaucage (1996).  J. Appl. Cryst., vol. 29, p134-146. 
     4301G Beaucage (1995).  J. Appl. Cryst., vol. 28, p717-728. 
     4302 
     4303G Beaucage (1996).  J. Appl. Cryst., vol. 29, p134-146. 
    43094304 
    43104305 
     
    44344429REFERENCE 
    44354430 
    4436 Mitsuhiro Shibayama, Toyoichi Tanaka, Charles C. Han, J. Chem. Phys. 
    4437 1992, 97 (9), 6829-6841. 
    4438  
    4439 Simon Mallam, Ferenc Horkay, Anne-Marie Hecht, Adrian R. Rennie, Erik 
    4440 Geissler, Macromolecules 1991, 24, 543-548. 
     4431Mitsuhiro Shibayama, Toyoichi Tanaka, Charles C Han, J. Chem. Phys. 1992, 97 (9), 6829-6841 
     4432 
     4433Simon Mallam, Ferenc Horkay, Anne-Marie Hecht, Adrian R Rennie, Erik Geissler, Macromolecules 1991, 24, 543-548 
    44414434 
    44424435 
     
    44584451REFERENCE 
    44594452 
    4460 H. Benoit,   J. Polymer Science.,  11, 596-599  (1953) 
     4453H Benoit,   J. Polymer Science.,  11, 596-599  (1953) 
    44614454 
    44624455 
     
    44974490REFERENCE 
    44984491 
    4499 J. K. Percus, J. Yevick, *J. Phys. Rev.*, 110, (1958) 1 
     4492J K Percus, J Yevick, *J. Phys. Rev.*, 110, (1958) 1 
    45004493 
    45014494 
     
    45214514where *r* is the distance from the center of the sphere of a radius *R*. 
    45224515 
    4523 For 2D plot, the wave transfer is defined as 
     4516For 2D data: The 2D scattering intensity is calculated in the same way as 1D, where the *q* vector is defined as 
    45244517 
    45254518.. image:: img/image040.GIF 
     
    45404533REFERENCE 
    45414534 
    4542 R. V. Sharma, K. C. Sharma, *Physica*, 89A (1977) 213 
     4535R V Sharma, K C Sharma, *Physica*, 89A (1977) 213 
    45434536 
    45444537 
     
    45604553multivalent salts. The counterions are also assumed to be monovalent. 
    45614554 
    4562 For 2D plot, the wave transfer is defined as 
     4555For 2D data: The 2D scattering intensity is calculated in the same way as 1D, where the *q* vector is defined as 
    45634556 
    45644557.. image:: img/image040.gif 
     
    45814574REFERENCE 
    45824575 
    4583 J. B. Hayter and J. Penfold, *Molecular Physics*, 42 (1981) 109-118 
    4584  
    4585 J. P. Hansen and J. B. Hayter, *Molecular Physics*, 46 (1982) 651-656 
     4576J B Hayter and J Penfold, *Molecular Physics*, 42 (1981) 109-118 
     4577 
     4578J P Hansen and J B Hayter, *Molecular Physics*, 46 (1982) 651-656 
    45864579 
    45874580 
     
    46194612until the optimization does not hit the constraints. 
    46204613 
    4621 For 2D plot, the wave transfer is defined as 
     4614For 2D data: The 2D scattering intensity is calculated in the same way as 1D, where the *q* vector is defined as 
    46224615 
    46234616.. image:: img/image040.GIF 
     
    46384631REFERENCE 
    46394632 
    4640 S. V. G. Menon, C. Manohar, and K. S. Rao, *J. Chem. Phys.*, 95(12) (1991) 9186-9190 
     4633S V G Menon, C Manohar, and K S Rao, *J. Chem. Phys.*, 95(12) (1991) 9186-9190 
    46414634 
    46424635 
Note: See TracChangeset for help on using the changeset viewer.