[deb7ee0] | 1 | double form_volume(double a_side, double b2a_ratio, double c2a_ratio); |
---|
| 2 | double Iq(double q, double sld, double solvent_sld, double a_side, |
---|
| 3 | double b2a_ratio, double c2a_ratio); |
---|
| 4 | double Iqxy(double qx, double qy, double sld, double solvent_sld, |
---|
| 5 | double a_side, double b2a_ratio, double c2a_ratio); |
---|
| 6 | |
---|
| 7 | double form_volume(double a_side, double b2a_ratio, double c2a_ratio) |
---|
| 8 | { |
---|
| 9 | double b_side = a_side * b2a_ratio; |
---|
| 10 | double c_side = a_side * c2a_ratio; |
---|
| 11 | double vol_shell = 2.0 * (a_side*b_side + a_side*c_side + b_side*c_side); |
---|
| 12 | return vol_shell; |
---|
| 13 | } |
---|
| 14 | |
---|
| 15 | double Iq(double q, |
---|
| 16 | double sld, |
---|
| 17 | double solvent_sld, |
---|
| 18 | double a_side, |
---|
| 19 | double b2a_ratio, |
---|
| 20 | double c2a_ratio) |
---|
| 21 | { |
---|
| 22 | double b_side = a_side * b2a_ratio; |
---|
| 23 | double c_side = a_side * c2a_ratio; |
---|
| 24 | double a_half = 0.5 * a_side; |
---|
| 25 | double b_half = 0.5 * b_side; |
---|
| 26 | double c_half = 0.5 * c_side; |
---|
| 27 | |
---|
| 28 | //Integration limits to use in Gaussian quadrature |
---|
| 29 | double v1a = 0.0; |
---|
| 30 | double v1b = 0.5 * M_PI; //theta integration limits |
---|
| 31 | double v2a = 0.0; |
---|
| 32 | double v2b = 0.5 * M_PI; //phi integration limits |
---|
| 33 | |
---|
| 34 | //Order of integration |
---|
| 35 | int nordi=76; |
---|
| 36 | int nordj=76; |
---|
| 37 | |
---|
| 38 | double sumi = 0.0; |
---|
| 39 | |
---|
| 40 | for(int i=0; i<nordi; i++) { |
---|
| 41 | |
---|
| 42 | double theta = 0.5 * ( Gauss76Z[i]*(v1b-v1a) + v1a + v1b ); |
---|
| 43 | |
---|
| 44 | // To check potential problems if denominator goes to zero here !!! |
---|
| 45 | double termAL_theta = 8.0*cos(q*c_half*cos(theta)) / (q*q*sin(theta)*sin(theta)); |
---|
| 46 | double termAT_theta = 8.0*sin(q*c_half*cos(theta)) / (q*q*sin(theta)*cos(theta)); |
---|
| 47 | |
---|
| 48 | double sumj = 0.0; |
---|
| 49 | |
---|
| 50 | for(int j=0; j<nordj; j++) { |
---|
| 51 | |
---|
| 52 | double phi = 0.5 * ( Gauss76Z[j]*(v2b-v2a) + v2a + v2b ); |
---|
| 53 | |
---|
| 54 | // Amplitude AL from eqn. (7c) |
---|
| 55 | double AL = termAL_theta * sin(q*a_half*sin(theta)*sin(phi)) * |
---|
| 56 | sin(q*b_half*sin(theta)*cos(phi)) / (sin(phi)*cos(phi)); |
---|
| 57 | |
---|
| 58 | // Amplitude AT from eqn. (9) |
---|
| 59 | double AT = termAT_theta * ( (cos(q*a_half*sin(theta)*sin(phi))*sin(q*b_half*sin(theta)*cos(phi))/cos(phi)) |
---|
| 60 | + (cos(q*b_half*sin(theta)*cos(phi))*sin(q*a_half*sin(theta)*sin(phi))/sin(phi)) ); |
---|
| 61 | |
---|
| 62 | sumj += Gauss76Wt[j] * (AL+AT)*(AL+AT); |
---|
| 63 | |
---|
| 64 | } |
---|
| 65 | |
---|
| 66 | sumj = 0.5 * (v2b-v2a) * sumj; |
---|
| 67 | sumi += Gauss76Wt[i] * sumj * sin(theta); |
---|
| 68 | |
---|
| 69 | } |
---|
| 70 | |
---|
| 71 | double answer = 0.5*(v1b-v1a)*sumi; |
---|
| 72 | |
---|
| 73 | // Normalize as in Eqn. (15) without the volume factor (as cancels with (V*DelRho)^2 normalization) |
---|
| 74 | // The factor 2 is due to the different theta integration limit (pi/2 instead of pi) |
---|
| 75 | answer *= (2.0/M_PI); |
---|
| 76 | |
---|
| 77 | // Multiply by contrast^2. Factor corresponding to volume^2 cancels with previous normalization. |
---|
| 78 | answer *= (sld-solvent_sld)*(sld-solvent_sld); |
---|
| 79 | |
---|
| 80 | // Convert from [1e-12 A-1] to [cm-1] |
---|
| 81 | answer *= 1.0e-4; |
---|
| 82 | |
---|
| 83 | return answer; |
---|
| 84 | |
---|
| 85 | } |
---|
| 86 | |
---|
| 87 | double Iqxy(double qx, double qy, |
---|
| 88 | double sld, |
---|
| 89 | double solvent_sld, |
---|
| 90 | double a_side, |
---|
| 91 | double b2a_ratio, |
---|
| 92 | double c2a_ratio) |
---|
| 93 | { |
---|
| 94 | double q = sqrt(qx*qx + qy*qy); |
---|
| 95 | double intensity = Iq(q, sld, solvent_sld, a_side, b2a_ratio, c2a_ratio); |
---|
| 96 | return intensity; |
---|
| 97 | } |
---|