#if !defined(HayterMSA_h)
#define HayterMSA_h

/**
 * Structure definition for screened Coulomb interaction
 */
 //[PYTHONCLASS] = HayterMSAStructure
 //[DISP_PARAMS] = radius
 //[DESCRIPTION] =<text>To calculate the structure factor (the Fourier transform   
 //                     of the pair correlation function g(r)) for 
 //                     a system of charged, spheroidal objects in    
 //                     a dielectric medium. When combined with an 
 //                     appropriate form factor, this allows 
 //                     for inclusion of the interparticle 
 //                     interference effects due to screened coulomb 
 //                     repulsion between charged particles.
 //                     (note: charge > 0 required.)
 //
 //                     Ref: JP Hansen and JB Hayter, Molecular 
 //                           Physics 46, 651-656 (1982).
 //
 //				</text>
 //[FIXED]= radius.width  
 
typedef struct {
    ///	Radius of particle [A]
    //  [DEFAULT]=radius=20.75 A
    double radius;

    /// charge
    //  [DEFAULT]=charge= 19
    double charge;

    /// Volume fraction
    //  [DEFAULT]=volfraction= 0.0192
    double volfraction;

	///	Temperature [K]
    //  [DEFAULT]=temperature= 318.16 K 
    double temperature;

	///	Monovalent salt concentration [M] 
    //  [DEFAULT]=saltconc= 0 
    double saltconc;

    ///	Dielectric constant of solvent 
    //  [DEFAULT]=dielectconst= 71.08 
    double dielectconst;
} HayterMSAParameters;



/// 1D scattering function
double HayterMSA_analytical_1D(HayterMSAParameters *pars, double q);

/// 2D scattering function
double HayterMSA_analytical_2D(HayterMSAParameters *pars, double q, double phi);
double HayterMSA_analytical_2DXY(HayterMSAParameters *pars, double qx, double qy);

#endif