Homec4science
Diffusion lammps (lammm-master) Browse

lammps/src/MANYBODY/pair_airebo.h
d3355b03dc0elammm-master

Last Change
Raw File

pair_airebo.h
View Options

/* ----------------------------------------------------------------------
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 PAIR_CLASS
PairStyle(airebo,PairAIREBO)
#else
#ifndef LMP_PAIR_AIREBO_H
#define LMP_PAIR_AIREBO_H
#include "pair.h"
#include "math.h"
#include "math_const.h"
namespace LAMMPS_NS {
class PairAIREBO : public Pair {
public:
PairAIREBO(class LAMMPS *);
virtual ~PairAIREBO();
virtual void compute(int, int);
virtual void settings(int, char **);
void coeff(int, char **);
void init_style();
double init_one(int, int);
double memory_usage();
protected:
int **pages; // neighbor list pages
int *map; // 0 (C), 1 (H), or -1 (NULL) for each type
int me;
int ljflag,torflag; // 0/1 if LJ,torsion terms included
int maxlocal; // size of numneigh, firstneigh arrays
int maxpage; // # of pages currently allocated
int pgsize; // size of neighbor page
int oneatom; // max # of neighbors for one atom
double cutlj; // user-specified LJ cutoff
double cutljrebosq; // cut for when to compute
// REBO neighs of ghost atoms
double **cutljsq; // LJ cutoffs for C,H types
double **lj1,**lj2,**lj3,**lj4; // pre-computed LJ coeffs for C,H types
double cut3rebo; // maximum distance for 3rd REBO neigh
int *REBO_numneigh; // # of pair neighbors for each atom
int **REBO_firstneigh; // ptr to 1st neighbor of each atom
double *closestdistsq; // closest owned atom dist to each ghost
double *nC,*nH; // sum of weighting fns with REBO neighs
double smin,Nmin,Nmax,NCmin,NCmax,thmin,thmax;
double rcmin[2][2],rcmax[2][2],rcmaxsq[2][2],rcmaxp[2][2];
double Q[2][2],alpha[2][2],A[2][2],rho[2][2],BIJc[2][2][3],Beta[2][2][3];
double rcLJmin[2][2],rcLJmax[2][2],rcLJmaxsq[2][2],bLJmin[2][2],bLJmax[2][2];
double epsilon[2][2],sigma[2][2],epsilonT[2][2];
// spline coefficients
double gCdom[5],gC1[4][6],gC2[4][6],gHdom[4],gH[3][6];
double pCCdom[2][2],pCHdom[2][2],pCC[4][4][16],pCH[4][4][16];
double piCCdom[3][2],piCHdom[3][2],piHHdom[3][2];
double piCC[4][4][9][64],piCH[4][4][9][64],piHH[4][4][9][64];
double Tijdom[3][2],Tijc[4][4][9][64];
// spline knot values
double PCCf[5][5],PCCdfdx[5][5],PCCdfdy[5][5],PCHf[5][5];
double PCHdfdx[5][5],PCHdfdy[5][5];
double piCCf[5][5][11],piCCdfdx[5][5][11];
double piCCdfdy[5][5][11],piCCdfdz[5][5][11];
double piCHf[5][5][11],piCHdfdx[5][5][11];
double piCHdfdy[5][5][11],piCHdfdz[5][5][11];
double piHHf[5][5][11],piHHdfdx[5][5][11];
double piHHdfdy[5][5][11],piHHdfdz[5][5][11];
double Tf[5][5][10],Tdfdx[5][5][10],Tdfdy[5][5][10],Tdfdz[5][5][10];
void REBO_neigh();
void FREBO(int, int);
void FLJ(int, int);
void TORSION(int, int);
double bondorder(int, int, double *, double, double, double **, int);
double bondorderLJ(int, int, double *, double, double,
double *, double, double **, int);
double gSpline(double, double, int, double *, double *);
double PijSpline(double, double, int, int, double *);
double piRCSpline(double, double, double, int, int, double *);
double TijSpline(double, double, double, double *);
void add_pages(int howmany=1);
void read_file(char *);
double Sp5th(double, double *, double *);
double Spbicubic(double, double, double *, double *);
double Sptricubic(double, double, double, double *, double *);
void spline_init();
void allocate();
// ----------------------------------------------------------------------
// S'(t) and S(t) cutoff functions
// added to header for inlining
// ----------------------------------------------------------------------
/* ----------------------------------------------------------------------
cutoff function Sprime
return cutoff and dX = derivative
no side effects
------------------------------------------------------------------------- */
inline double Sp(double Xij, double Xmin, double Xmax, double &dX) const {
double cutoff;
double t = (Xij-Xmin) / (Xmax-Xmin);
if (t <= 0.0) {
cutoff = 1.0;
dX = 0.0;
} else if (t >= 1.0) {
cutoff = 0.0;
dX = 0.0;
} else {
cutoff = 0.5 * (1.0+cos(t*MathConst::MY_PI));
dX = (-0.5*MathConst::MY_PI*sin(t*MathConst::MY_PI)) / (Xmax-Xmin);
}
return cutoff;
};
/* ----------------------------------------------------------------------
LJ cutoff function Sp2
return cutoff and dX = derivative
no side effects
------------------------------------------------------------------------- */
inline double Sp2(double Xij, double Xmin, double Xmax, double &dX) const {
double cutoff;
double t = (Xij-Xmin) / (Xmax-Xmin);
if (t <= 0.0) {
cutoff = 1.0;
dX = 0.0;
} else if (t >= 1.0) {
cutoff = 0.0;
dX = 0.0;
} else {
cutoff = (1.0-(t*t*(3.0-2.0*t)));
dX = 6.0*(t*t-t) / (Xmax-Xmin);
}
return cutoff;
};
/* kronecker delta function returning a double */
inline double kronecker(const int a, const int b) const {
return (a == b) ? 1.0 : 0.0;
};
};
}
#endif
#endif
/* ERROR/WARNING messages:
E: Illegal ... command
Self-explanatory. Check the input script syntax and compare to the
documentation for the command. You can use -echo screen as a
command-line option when running LAMMPS to see the offending line.
E: Incorrect args for pair coefficients
Self-explanatory. Check the input script or data file.
E: Pair style AIREBO requires atom IDs
This is a requirement to use the AIREBO potential.
E: Pair style AIREBO requires newton pair on
See the newton command. This is a restriction to use the AIREBO
potential.
E: All pair coeffs are not set
All pair coefficients must be set in the data file or by the
pair_coeff command before running a simulation.
E: Neighbor list overflow, boost neigh_modify one or page
There are too many neighbors of a single atom. Use the neigh_modify
command to increase the neighbor page size and the max number of
neighbors allowed for one atom.
E: Cannot open AIREBO potential file %s
The specified AIREBO potential file cannot be opened. Check that the
path and name are correct.
*/
c4science · Help