/*   []----------------------------------------[]
      |                 Rydberg.h              |
     []----------------------------------------[]
      |                                        |
      |   AUTHOR:    MFSomers 2005.            |
      |   USE:       Defines a Rydberg type    |
      |               interaction...           |
      |                                        |
     []----------------------------------------[]
*/

// Copyright (C) 2005 M.F. Somers, Theoretical Chemistry Department, Leiden University
//
// This is free software; you can redistribute it and/or modify it under the terms of
// the GNU Lesser General Public License as published by the Free Software Foundation.
//
// http://www.gnu.org/licenses/lgpl.txt

#if !defined(__RYDBERG_INCLUDED__)

#define __RYDBERG_INCLUDED__

#include "Global.h"
#include "Vector.h"
#include "Constants.h"
#include "ClassicalDynamics.h"
#include "PointPair.h"

/* --------------------------------------------------------- */
/* Defines a Rydberg pointpair interaction between particles */

class   RydbergInteraction;
 typedef RydbergInteraction *RydbergInteractionPointer;

class RydbergInteraction : public PointPairInteraction
                         {
		 	  public:
			     
			  inline RydbergInteraction( double TheD, double TheR, double TheA1,
			                             double TheA2, double TheA3, double TheGamma,
						     unsigned int TheId = GET_NEW_ID, Vector *UsePeriodicBox = NULL ) : PointPairInteraction( TheId, UsePeriodicBox )
			  {
			   D = TheD;
			   R = TheR;
			   Gamma = TheGamma;
			   A1 = TheA1;
			   A2 = TheA2;
			   A3 = TheA3;
			   Type = ARydbergInteraction;
			  }
			  inline RydbergInteraction( RydbergInteraction& I ) : PointPairInteraction( I )
			  {
			   D = I.D;
			   R = I.R;
			   Gamma = I.Gamma;
			   A1 = I.A1;
			   A2 = I.A2;
			   A3 = I.A3;			   
			  }

          	          virtual RydbergInteraction& operator=( RydbergInteraction& I )
			  {
			   if( &I == &(*this) ) return( (*this) );
			   PointPairInteraction::operator=( I );
			   D = I.D;
			   R = I.R;
			   Gamma = I.Gamma;
			   A1 = I.A1;
			   A2 = I.A2;
			   A3 = I.A3;		   
			   return( (*this) );
			  } 			    
		          virtual RydbergInteractionPointer Clone()
		          {
		           return( new RydbergInteraction( (*this) ) );
		          }
		          virtual RydbergInteractionPointer Create( double TheD = 1.0, double TheR = 1.0, double TheA1 = 1.0,
			                                            double TheA2 = 1.0, double TheA3 = 1.0, double TheGamma = 1.0,
						                    unsigned int TheId = GET_NEW_ID, Vector *UsePeriodicBox = NULL )
		          {
		           return( new RydbergInteraction( TheD, TheR, TheA1, TheA2, TheA3, TheGamma, TheId, UsePeriodicBox ) );
		          }
				    
			  virtual double PointPairPotential( Particle& P1, Particle& P2 );
			  virtual Vector PointPairForce( Particle& P1, Particle& P2 );
			  
			  double D, R, A1, A2, A3, Gamma;       /* V(r) = D-D*(1+A1*(r-R)+A2*(r-R)^2+A3*(r-R)^3)*EXP(-Gamma*(r-R)) */
			 };
			   
/* --------------------------------------------------------- */

#endif