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/* -*- 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.
------------------------------------------------------------------------- */
#ifndef LMP_FIX_NH_H
#define LMP_FIX_NH_H
#include "fix.h"
namespace LAMMPS_NS {
class FixNH : public Fix {
public:
FixNH(class LAMMPS *, int, char **);
virtual ~FixNH();
int setmask();
virtual void init();
virtual void setup(int);
virtual void initial_integrate(int);
virtual void final_integrate();
void initial_integrate_respa(int, int, int);
void final_integrate_respa(int, int);
virtual void pre_exchange();
double compute_scalar();
virtual double compute_vector(int);
void write_restart(FILE *);
virtual int pack_restart_data(double *); // pack restart data
virtual void restart(char *);
int modify_param(int, char **);
void reset_target(double);
void reset_dt();
virtual void *extract(const char*,int &);
double memory_usage();
protected:
int dimension,which;
double dtv,dtf,dthalf,dt4,dt8,dto;
double boltz,nktv2p,tdof;
double vol0; // reference volume
double t0; // reference temperature
// used for barostat mass
double t_start,t_stop;
double t_current,t_target,ke_target;
double t_freq;
int tstat_flag; // 1 if control T
int pstat_flag; // 1 if control P
int pstyle,pcouple,allremap;
int p_flag[6]; // 1 if control P on this dim, 0 if not
double p_start[6],p_stop[6];
double p_freq[6],p_target[6];
double omega[6],omega_dot[6];
double omega_mass[6];
double p_current[6];
double drag,tdrag_factor; // drag factor on particle thermostat
double pdrag_factor; // drag factor on barostat
int kspace_flag; // 1 if KSpace invoked, 0 if not
int nrigid; // number of rigid fixes
int dilate_group_bit; // mask for dilation group
int *rfix; // indices of rigid fixes
char *id_dilate; // group name to dilate
class Irregular *irregular; // for migrating atoms after box flips
int nlevels_respa;
double *step_respa;
char *id_temp,*id_press;
class Compute *temperature,*pressure;
int tcomputeflag,pcomputeflag; // 1 = compute was created by fix
// 0 = created externally
double *eta,*eta_dot; // chain thermostat for particles
double *eta_dotdot;
double *eta_mass;
int mtchain; // length of chain
int mtchain_default_flag; // 1 = mtchain is default
double *etap; // chain thermostat for barostat
double *etap_dot;
double *etap_dotdot;
double *etap_mass;
int mpchain; // length of chain
int mtk_flag; // 0 if using Hoover barostat
int pdim; // number of barostatted dims
double p_freq_max; // maximum barostat frequency
double p_hydro; // hydrostatic target pressure
int nc_tchain,nc_pchain;
double factor_eta;
double sigma[6]; // scaled target stress
double fdev[6]; // deviatoric force on barostat
int deviatoric_flag; // 0 if target stress tensor is hydrostatic
double h0_inv[6]; // h_inv of reference (zero strain) box
int nreset_h0; // interval for resetting h0
double mtk_term1,mtk_term2; // Martyna-Tobias-Klein corrections
int eta_mass_flag; // 1 if eta_mass updated, 0 if not.
int omega_mass_flag; // 1 if omega_mass updated, 0 if not.
int etap_mass_flag; // 1 if etap_mass updated, 0 if not.
int dipole_flag; // 1 if dipole is updated, 0 if not.
int dlm_flag; // 1 if using the DLM rotational integrator, 0 if not
int scaleyz; // 1 if yz scaled with lz
int scalexz; // 1 if xz scaled with lz
int scalexy; // 1 if xy scaled with ly
int flipflag; // 1 if box flips are invoked as needed
int pre_exchange_flag; // set if pre_exchange needed for box flips
double fixedpoint[3]; // location of dilation fixed-point
void couple();
virtual void remap();
void nhc_temp_integrate();
void nhc_press_integrate();
virtual void nve_x(); // may be overwritten by child classes
virtual void nve_v();
virtual void nh_v_press();
virtual void nh_v_temp();
virtual void compute_temp_target();
virtual int size_restart_global();
void compute_sigma();
void compute_deviatoric();
double compute_strain_energy();
void compute_press_target();
void nh_omega_dot();
};
}
#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: Target temperature for fix nvt/npt/nph cannot be 0.0
Self-explanatory.
E: Invalid fix nvt/npt/nph command for a 2d simulation
Cannot control z dimension in a 2d model.
E: Fix nvt/npt/nph dilate group ID does not exist
Self-explanatory.
E: Invalid fix nvt/npt/nph command pressure settings
If multiple dimensions are coupled, those dimensions must be
specified.
E: Cannot use fix nvt/npt/nph on a non-periodic dimension
When specifying a diagonal pressure component, the dimension must be
periodic.
E: Cannot use fix nvt/npt/nph on a 2nd non-periodic dimension
When specifying an off-diagonal pressure component, the 2nd of the two
dimensions must be periodic. E.g. if the xy component is specified,
then the y dimension must be periodic.
E: Cannot use fix nvt/npt/nph with yz scaling when z is non-periodic dimension
The 2nd dimension in the barostatted tilt factor must be periodic.
E: Cannot use fix nvt/npt/nph with xz scaling when z is non-periodic dimension
The 2nd dimension in the barostatted tilt factor must be periodic.
E: Cannot use fix nvt/npt/nph with xy scaling when y is non-periodic dimension
The 2nd dimension in the barostatted tilt factor must be periodic.
E: Cannot use fix nvt/npt/nph with both yz dynamics and yz scaling
Self-explanatory.
E: Cannot use fix nvt/npt/nph with both xz dynamics and xz scaling
Self-explanatory.
E: Cannot use fix nvt/npt/nph with both xy dynamics and xy scaling
Self-explanatory.
E: Can not specify Pxy/Pxz/Pyz in fix nvt/npt/nph with non-triclinic box
Only triclinic boxes can be used with off-diagonal pressure components.
See the region prism command for details.
E: Invalid fix nvt/npt/nph pressure settings
Settings for coupled dimensions must be the same.
E: Using update dipole flag requires atom style sphere
Self-explanatory.
E: Using update dipole flag requires atom attribute mu
Self-explanatory.
E: Fix nvt/npt/nph damping parameters must be > 0.0
Self-explanatory.
E: Cannot use fix npt and fix deform on same component of stress tensor
This would be changing the same box dimension twice.
E: Temperature ID for fix nvt/npt does not exist
Self-explanatory.
E: Pressure ID for fix npt/nph does not exist
Self-explanatory.
E: Non-numeric pressure - simulation unstable
UNDOCUMENTED
E: Fix npt/nph has tilted box too far in one step - periodic cell is too far from equilibrium state
Self-explanatory. The change in the box tilt is too extreme
on a short timescale.
E: Could not find fix_modify temperature ID
The compute ID for computing temperature does not exist.
E: Fix_modify temperature ID does not compute temperature
The compute ID assigned to the fix must compute temperature.
W: Temperature for fix modify is not for group all
The temperature compute is being used with a pressure calculation
which does operate on group all, so this may be inconsistent.
E: Pressure ID for fix modify does not exist
Self-explanatory.
E: Could not find fix_modify pressure ID
The compute ID for computing pressure does not exist.
E: Fix_modify pressure ID does not compute pressure
The compute ID assigned to the fix must compute pressure.
U: The dlm flag must be used with update dipole
Self-explanatory.
*/