| 134 |
|
return temperature; |
| 135 |
|
} |
| 136 |
|
|
| 137 |
< |
double Thermo::getPressure(){ |
| 138 |
< |
// returns pressure in units amu*fs^-2*Ang^-1 |
| 137 |
> |
double Thermo::getPressure() { |
| 138 |
> |
// returns the pressure in units of atm |
| 139 |
> |
// Relies on the calculation of the full molecular pressure tensor |
| 140 |
> |
|
| 141 |
> |
const double p_convert = 1.63882576e8; |
| 142 |
> |
double press[9]; |
| 143 |
> |
double pressure; |
| 144 |
> |
|
| 145 |
> |
this->getPressureTensor(press); |
| 146 |
> |
|
| 147 |
> |
pressure = p_convert * (press[0] + press[4] + press[8]) / 3.0; |
| 148 |
> |
|
| 149 |
> |
return pressure; |
| 150 |
> |
} |
| 151 |
> |
|
| 152 |
> |
|
| 153 |
> |
void Thermo::getPressureTensor(double press[9]){ |
| 154 |
> |
// returns pressure tensor in units amu*fs^-2*Ang^-1 |
| 155 |
|
// routine derived via viral theorem description in: |
| 156 |
|
// Paci, E. and Marchi, M. J.Phys.Chem. 1996, 100, 4314-4322 |
| 157 |
|
|
| 158 |
|
const double e_convert = 4.184e-4; |
| 159 |
< |
const double p_convert = 1.63882576e8; |
| 160 |
< |
double molmass; |
| 159 |
> |
|
| 160 |
> |
double molmass, volume; |
| 161 |
|
double vcom[3]; |
| 162 |
< |
double p_local, p_sum, p_mol, virial; |
| 162 |
> |
double p_local[9], p_global[9]; |
| 163 |
|
double theBox[3]; |
| 164 |
|
double* tau; |
| 165 |
|
int i, nMols; |
| 170 |
|
tau = entry_plug->tau; |
| 171 |
|
|
| 172 |
|
// use velocities of molecular centers of mass and molecular masses: |
| 173 |
< |
p_local = 0.0; |
| 173 |
> |
for (i=0; i < 9; i++) { |
| 174 |
> |
p_local[i] = 0.0; |
| 175 |
> |
p_global[i] = 0.0; |
| 176 |
> |
} |
| 177 |
|
|
| 178 |
|
for (i=0; i < nMols; i++) { |
| 179 |
|
molmass = molecules[i].getCOMvel(vcom); |
| 180 |
< |
p_local += (vcom[0]*vcom[0] + vcom[1]*vcom[1] + vcom[2]*vcom[2]) * molmass; |
| 180 |
> |
|
| 181 |
> |
p_local[0] += molmass * (vcom[0] * vcom[0]); |
| 182 |
> |
p_local[1] += molmass * (vcom[0] * vcom[1]); |
| 183 |
> |
p_local[2] += molmass * (vcom[0] * vcom[2]); |
| 184 |
> |
p_local[3] += molmass * (vcom[1] * vcom[0]); |
| 185 |
> |
p_local[4] += molmass * (vcom[1] * vcom[1]); |
| 186 |
> |
p_local[5] += molmass * (vcom[1] * vcom[2]); |
| 187 |
> |
p_local[6] += molmass * (vcom[2] * vcom[0]); |
| 188 |
> |
p_local[7] += molmass * (vcom[2] * vcom[1]); |
| 189 |
> |
p_local[8] += molmass * (vcom[2] * vcom[2]); |
| 190 |
|
} |
| 191 |
|
|
| 192 |
|
// Get total for entire system from MPI. |
| 193 |
|
|
| 194 |
|
#ifdef IS_MPI |
| 195 |
< |
MPI_Allreduce(&p_local,&p_sum,1,MPI_DOUBLE, MPI_SUM, MPI_COMM_WORLD); |
| 195 |
> |
MPI_Allreduce(p_local,p_global,9,MPI_DOUBLE, MPI_SUM, MPI_COMM_WORLD); |
| 196 |
|
#else |
| 197 |
< |
p_sum = p_local; |
| 197 |
> |
for (i=0; i<9; i++) { |
| 198 |
> |
p_global[i] = p_local[i]; |
| 199 |
> |
} |
| 200 |
|
#endif // is_mpi |
| 201 |
|
|
| 172 |
– |
virial = tau[0] + tau[4] + tau[8]; |
| 202 |
|
entry_plug->getBox(theBox); |
| 203 |
|
|
| 204 |
< |
p_mol = p_convert * (p_sum - virial*e_convert) / |
| 176 |
< |
(3.0 * theBox[0] * theBox[1]* theBox[2]); |
| 204 |
> |
volume = theBox[0] * theBox[1] * theBox[2]; |
| 205 |
|
|
| 206 |
< |
return p_mol; |
| 206 |
> |
for(i=0; i<9; i++) { |
| 207 |
> |
press[i] = (p_global[i] - tau[i]*e_convert) / volume; |
| 208 |
> |
} |
| 209 |
|
} |
| 210 |
|
|
| 211 |
|
void Thermo::velocitize() { |
