| 1 | /* | 
| 2 | * Copyright (c) 2005 The University of Notre Dame. All Rights Reserved. | 
| 3 | * | 
| 4 | * The University of Notre Dame grants you ("Licensee") a | 
| 5 | * non-exclusive, royalty free, license to use, modify and | 
| 6 | * redistribute this software in source and binary code form, provided | 
| 7 | * that the following conditions are met: | 
| 8 | * | 
| 9 | * 1. Redistributions of source code must retain the above copyright | 
| 10 | *    notice, this list of conditions and the following disclaimer. | 
| 11 | * | 
| 12 | * 2. Redistributions in binary form must reproduce the above copyright | 
| 13 | *    notice, this list of conditions and the following disclaimer in the | 
| 14 | *    documentation and/or other materials provided with the | 
| 15 | *    distribution. | 
| 16 | * | 
| 17 | * This software is provided "AS IS," without a warranty of any | 
| 18 | * kind. All express or implied conditions, representations and | 
| 19 | * warranties, including any implied warranty of merchantability, | 
| 20 | * fitness for a particular purpose or non-infringement, are hereby | 
| 21 | * excluded.  The University of Notre Dame and its licensors shall not | 
| 22 | * be liable for any damages suffered by licensee as a result of | 
| 23 | * using, modifying or distributing the software or its | 
| 24 | * derivatives. In no event will the University of Notre Dame or its | 
| 25 | * licensors be liable for any lost revenue, profit or data, or for | 
| 26 | * direct, indirect, special, consequential, incidental or punitive | 
| 27 | * damages, however caused and regardless of the theory of liability, | 
| 28 | * arising out of the use of or inability to use software, even if the | 
| 29 | * University of Notre Dame has been advised of the possibility of | 
| 30 | * such damages. | 
| 31 | * | 
| 32 | * SUPPORT OPEN SCIENCE!  If you use OpenMD or its source code in your | 
| 33 | * research, please cite the appropriate papers when you publish your | 
| 34 | * work.  Good starting points are: | 
| 35 | * | 
| 36 | * [1]  Meineke, et al., J. Comp. Chem. 26, 252-271 (2005). | 
| 37 | * [2]  Fennell & Gezelter, J. Chem. Phys. 124, 234104 (2006). | 
| 38 | * [3]  Sun, Lin & Gezelter, J. Chem. Phys. 128, 234107 (2008). | 
| 39 | * [4]  Kuang & Gezelter,  J. Chem. Phys. 133, 164101 (2010). | 
| 40 | * [5]  Vardeman, Stocker & Gezelter, J. Chem. Theory Comput. 7, 834 (2011). | 
| 41 | */ | 
| 42 |  | 
| 43 | #include "NPTi.hpp" | 
| 44 | #include "brains/SimInfo.hpp" | 
| 45 | #include "brains/Thermo.hpp" | 
| 46 | #include "integrators/NPT.hpp" | 
| 47 | #include "primitives/Molecule.hpp" | 
| 48 | #include "utils/PhysicalConstants.hpp" | 
| 49 | #include "utils/simError.h" | 
| 50 |  | 
| 51 | namespace OpenMD { | 
| 52 |  | 
| 53 | // Basic isotropic thermostating and barostating via the Melchionna | 
| 54 | // modification of the Hoover algorithm: | 
| 55 | // | 
| 56 | //    Melchionna, S., Ciccotti, G., and Holian, B. L., 1993, | 
| 57 | //       Molec. Phys., 78, 533. | 
| 58 | // | 
| 59 | //           and | 
| 60 | // | 
| 61 | //    Hoover, W. G., 1986, Phys. Rev. A, 34, 2499. | 
| 62 |  | 
| 63 | NPTi::NPTi ( SimInfo *info) : NPT(info){ | 
| 64 |  | 
| 65 | } | 
| 66 |  | 
| 67 | void NPTi::evolveEtaA() { | 
| 68 | eta += dt2 * ( instaVol * (instaPress - targetPressure) / | 
| 69 | (PhysicalConstants::pressureConvert*NkBT*tb2)); | 
| 70 | oldEta = eta; | 
| 71 | } | 
| 72 |  | 
| 73 | void NPTi::evolveEtaB() { | 
| 74 |  | 
| 75 | prevEta = eta; | 
| 76 | eta = oldEta + dt2 * ( instaVol * (instaPress - targetPressure) / | 
| 77 | (PhysicalConstants::pressureConvert*NkBT*tb2)); | 
| 78 | } | 
| 79 |  | 
| 80 | void NPTi::calcVelScale() { | 
| 81 | vScale = thermostat.first + eta; | 
| 82 | } | 
| 83 |  | 
| 84 | void NPTi::getVelScaleA(Vector3d& sc, const Vector3d& vel) { | 
| 85 | sc = vel * vScale; | 
| 86 | } | 
| 87 |  | 
| 88 | void NPTi::getVelScaleB(Vector3d& sc, int index ){ | 
| 89 | sc = oldVel[index] * vScale; | 
| 90 | } | 
| 91 |  | 
| 92 |  | 
| 93 | void NPTi::getPosScale(const Vector3d& pos, const Vector3d& COM, | 
| 94 | int index, Vector3d& sc){ | 
| 95 | /**@todo*/ | 
| 96 | sc  = (oldPos[index] + pos)/(RealType)2.0 -COM; | 
| 97 | sc *= eta; | 
| 98 | } | 
| 99 |  | 
| 100 | void NPTi::scaleSimBox(){ | 
| 101 |  | 
| 102 | RealType scaleFactor; | 
| 103 |  | 
| 104 | scaleFactor = exp(dt*eta); | 
| 105 |  | 
| 106 | if ((scaleFactor > 1.1) || (scaleFactor < 0.9)) { | 
| 107 | sprintf( painCave.errMsg, | 
| 108 | "NPTi error: Attempting a Box scaling of more than 10 percent" | 
| 109 | " check your tauBarostat, as it is probably too small!\n" | 
| 110 | " eta = %lf, scaleFactor = %lf\n", eta, scaleFactor | 
| 111 | ); | 
| 112 | painCave.isFatal = 1; | 
| 113 | simError(); | 
| 114 | } else { | 
| 115 | Mat3x3d hmat = snap->getHmat(); | 
| 116 | hmat *= scaleFactor; | 
| 117 | snap->setHmat(hmat); | 
| 118 | } | 
| 119 |  | 
| 120 | } | 
| 121 |  | 
| 122 | bool NPTi::etaConverged() { | 
| 123 |  | 
| 124 | return ( fabs(prevEta - eta) <= etaTolerance ); | 
| 125 | } | 
| 126 |  | 
| 127 | RealType NPTi::calcConservedQuantity(){ | 
| 128 |  | 
| 129 | thermostat = snap->getThermostat(); | 
| 130 | loadEta(); | 
| 131 | // We need NkBT a lot, so just set it here: This is the RAW number | 
| 132 | // of integrableObjects, so no subtraction or addition of constraints or | 
| 133 | // orientational degrees of freedom: | 
| 134 | NkBT = info_->getNGlobalIntegrableObjects()*PhysicalConstants::kB *targetTemp; | 
| 135 |  | 
| 136 | // fkBT is used because the thermostat operates on more degrees of freedom | 
| 137 | // than the barostat (when there are particles with orientational degrees | 
| 138 | // of freedom). | 
| 139 | fkBT = info_->getNdf()*PhysicalConstants::kB *targetTemp; | 
| 140 |  | 
| 141 | RealType conservedQuantity; | 
| 142 | RealType Energy; | 
| 143 | RealType thermostat_kinetic; | 
| 144 | RealType thermostat_potential; | 
| 145 | RealType barostat_kinetic; | 
| 146 | RealType barostat_potential; | 
| 147 |  | 
| 148 | Energy =thermo.getTotalEnergy(); | 
| 149 |  | 
| 150 | thermostat_kinetic = fkBT* tt2 * thermostat.first * | 
| 151 | thermostat.first / (2.0 * PhysicalConstants::energyConvert); | 
| 152 |  | 
| 153 | thermostat_potential = fkBT* thermostat.second / PhysicalConstants::energyConvert; | 
| 154 |  | 
| 155 |  | 
| 156 | barostat_kinetic = 3.0 * NkBT * tb2 * eta * eta /(2.0 * PhysicalConstants::energyConvert); | 
| 157 |  | 
| 158 | barostat_potential = (targetPressure * thermo.getVolume() / PhysicalConstants::pressureConvert) / | 
| 159 | PhysicalConstants::energyConvert; | 
| 160 |  | 
| 161 | conservedQuantity = Energy + thermostat_kinetic + thermostat_potential + | 
| 162 | barostat_kinetic + barostat_potential; | 
| 163 |  | 
| 164 | return conservedQuantity; | 
| 165 | } | 
| 166 |  | 
| 167 | void NPTi::loadEta() { | 
| 168 | Mat3x3d etaMat = snap->getBarostat(); | 
| 169 | eta = etaMat(0,0); | 
| 170 | //if (fabs(etaMat(1,1) - eta) >= OpenMD::epsilon || fabs(etaMat(1,1) - eta) >= OpenMD::epsilon || !etaMat.isDiagonal()) { | 
| 171 | //    sprintf( painCave.errMsg, | 
| 172 | //             "NPTi error: the diagonal elements of  eta matrix are not the same or etaMat is not a diagonal matrix"); | 
| 173 | //    painCave.isFatal = 1; | 
| 174 | //    simError(); | 
| 175 | //} | 
| 176 | } | 
| 177 |  | 
| 178 | void NPTi::saveEta() { | 
| 179 | Mat3x3d etaMat(0.0); | 
| 180 | etaMat(0, 0) = eta; | 
| 181 | etaMat(1, 1) = eta; | 
| 182 | etaMat(2, 2) = eta; | 
| 183 | snap->setBarostat(etaMat); | 
| 184 | } | 
| 185 | } |