/**********************************************************************

molchrg.h - Assign Gasteiger partial charges.

Copyright (C) 1998-2001 by OpenEye Scientific Software, Inc.

Some portions Copyright (C) 2001-2005 by Geoffrey R. Hutchison

This file is part of the Open Babel project.

For more information, see <http://openbabel.org/>

This program is free software; you can redistribute it and/or modify

it under the terms of the GNU General Public License as published by

the Free Software Foundation version 2 of the License.

This program is distributed in the hope that it will be useful,

but WITHOUT ANY WARRANTY; without even the implied warranty of

MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

GNU General Public License for more details.

***********************************************************************/

#ifndef OB_MOLCHRG_H

#define OB_MOLCHRG_H

#include <openbabel/babelconfig.h>

#include <vector>

namespace OpenBabel

{

  // Foward declarations

  class OBMol;

  class OBAtom;

//! \class GasteigerState molchrg.h <openbabel/molchrg.h>

//! \brief Helper class for OBGastChrg which stores the Gasteiger states of a given atom

class OBAPI GasteigerState

{

public:

    GasteigerState();

    ~GasteigerState() {}

    void SetValues(double _a,double _b,double _c,double _q)

    {

        a = _a;

        b = _b;

        c = _c;

        denom=a+b+c;

        q = _q;

    }

    double a, b, c;

    double denom;

    double chi;

    double q;

};

// class introduction in molchrg.cpp

class OBAPI OBGastChrg

{

  std::vector <GasteigerState*> _gsv; //!< vector of internal GasteigerState (for each atom)

    void InitialPartialCharges(OBMol &);

    bool GasteigerSigmaChi(OBAtom *,double &,double &,double &);

public:

    OBGastChrg()    {}

    ~OBGastChrg();

    //! Assign partial charges to this OBMol, setting each OBAtom partial charge

    bool AssignPartialCharges(OBMol &);

    //! Resize the internal GasteigerState vector to match the size of the molecule

    void GSVResize(int);

};

}

#define OB_GASTEIGER_DENOM  20.02

#define OB_GASTEIGER_DAMP   0.5

#define OB_GASTEIGER_ITERS  6

#endif // OB_MOLCHRG_H

//! \file molchrg.h

//! \brief Assign Gasteiger partial charges.