lammps/src/fix_rigid_nvt.h

73 lines
2.0 KiB
C++

/* ----------------------------------------------------------------------
LAMMPS - Large-scale Atomic/Molecular Massively Parallel Simulator
http://lammps.sandia.gov, Sandia National Laboratories
Steve Plimpton, sjplimp@sandia.gov
Copyright (2003) Sandia Corporation. Under the terms of Contract
DE-AC04-94AL85000 with Sandia Corporation, the U.S. Government retains
certain rights in this software. This software is distributed under
the GNU General Public License.
See the README file in the top-level LAMMPS directory.
------------------------------------------------------------------------- */
#ifdef FIX_CLASS
FixStyle(rigid/nvt,FixRigidNVT)
#else
#ifndef LMP_FIX_RIGID_NVT_H
#define LMP_FIX_RIGID_NVT_H
#include "fix_rigid.h"
namespace LAMMPS_NS {
class FixRigidNVT : public FixRigid {
public:
FixRigidNVT(class LAMMPS *, int, char **);
~FixRigidNVT();
void init();
void setup(int);
void initial_integrate(int);
void final_integrate();
void write_restart(FILE *);
void restart(char *);
void reset_target(double);
private:
double **conjqm; // conjugate quaternion momentum
double boltz; // boltzman constant
double t_target;
int nf_t,nf_r; // trans/rot degrees of freedom
double *w,*wdti1,*wdti2,*wdti4; // Yoshida-Suzuki coefficients
double *q_t,*q_r; // trans/rot thermostat masses
double *eta_t,*eta_r; // trans/rot thermostat positions
double *eta_dot_t,*eta_dot_r; // trans/rot thermostat velocities
double *f_eta_t,*f_eta_r; // trans/rot thermostat forces
void update_nhcp(double, double);
inline double maclaurin_series(double);
void allocate_chain();
void allocate_order();
void deallocate_chain();
void deallocate_order();
};
inline double FixRigidNVT::maclaurin_series(double x)
{
double x2,x4;
x2 = x * x;
x4 = x2 * x2;
return (1.0 + (1.0/6.0) * x2 + (1.0/120.0) * x4 + (1.0/5040.0) * x2 * x4 +
(1.0/362880.0) * x4 * x4);
}
}
#endif
#endif