| 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, 24107 (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 | #include "perturbations/ElectricField.hpp" | 
| 43 | #include "types/FixedChargeAdapter.hpp" | 
| 44 | #include "types/FluctuatingChargeAdapter.hpp" | 
| 45 | #include "types/MultipoleAdapter.hpp" | 
| 46 | #include "primitives/Molecule.hpp" | 
| 47 | #include "nonbonded/NonBondedInteraction.hpp" | 
| 48 |  | 
| 49 | namespace OpenMD { | 
| 50 |  | 
| 51 | ElectricField::ElectricField(SimInfo* info) : info_(info), | 
| 52 | doElectricField(false), | 
| 53 | doParticlePot(false), | 
| 54 | initialized(false) { | 
| 55 | simParams = info_->getSimParams(); | 
| 56 | } | 
| 57 |  | 
| 58 | void ElectricField::initialize() { | 
| 59 | if (simParams->haveElectricField()) { | 
| 60 | doElectricField = true; | 
| 61 | EF = simParams->getElectricField(); | 
| 62 | } | 
| 63 | int storageLayout_ = info_->getSnapshotManager()->getStorageLayout(); | 
| 64 | if (storageLayout_ & DataStorage::dslParticlePot) doParticlePot = true; | 
| 65 | initialized = true; | 
| 66 | } | 
| 67 |  | 
| 68 | void ElectricField::applyPerturbation() { | 
| 69 | if (!initialized) initialize(); | 
| 70 |  | 
| 71 | SimInfo::MoleculeIterator i; | 
| 72 | Molecule::AtomIterator  j; | 
| 73 | Molecule* mol; | 
| 74 | Atom* atom; | 
| 75 | potVec longRangePotential(0.0); | 
| 76 | Vector3d dip; | 
| 77 | Vector3d trq; | 
| 78 | Vector3d EFfrc; | 
| 79 | Vector3d pos; | 
| 80 | RealType chrg; | 
| 81 | RealType pot, fieldPot, moment; | 
| 82 | RealType chrgToKcal = 23.0609; | 
| 83 | RealType debyeToKcal = 4.8018969509; | 
| 84 | bool isCharge; | 
| 85 |  | 
| 86 | if (doElectricField) { | 
| 87 | fieldPot = 0.0; | 
| 88 |  | 
| 89 | for (mol = info_->beginMolecule(i); mol != NULL; mol = info_->nextMolecule(i)) { | 
| 90 | for (atom = mol->beginAtom(j); atom != NULL; | 
| 91 | atom = mol->nextAtom(j)) { | 
| 92 | isCharge = false; | 
| 93 | chrg = 0.0; | 
| 94 |  | 
| 95 | FixedChargeAdapter fca = FixedChargeAdapter(atom->getAtomType()); | 
| 96 | if ( fca.isFixedCharge() ) { | 
| 97 | isCharge = true; | 
| 98 | chrg = fca.getCharge(); | 
| 99 | } | 
| 100 |  | 
| 101 | FluctuatingChargeAdapter fqa = FluctuatingChargeAdapter(atom->getAtomType()); | 
| 102 | if ( fqa.isFluctuatingCharge() ) { | 
| 103 | isCharge = true; | 
| 104 | chrg += atom->getFlucQPos(); | 
| 105 | } | 
| 106 |  | 
| 107 | if (isCharge) { | 
| 108 | EFfrc = EF*chrg; | 
| 109 | EFfrc *= chrgToKcal; | 
| 110 | atom->addFrc(EFfrc); | 
| 111 | // totally ad-hoc choice of the origin for potential calculation | 
| 112 | pos = atom->getPos(); | 
| 113 | pot = -dot(pos, EFfrc); | 
| 114 | if (doParticlePot) { | 
| 115 | atom->addParticlePot(pot); | 
| 116 | } | 
| 117 | fieldPot += pot; | 
| 118 | } | 
| 119 |  | 
| 120 | MultipoleAdapter ma = MultipoleAdapter(atom->getAtomType()); | 
| 121 | if (ma.isDipole() ) { | 
| 122 | Vector3d u_i = atom->getElectroFrame().getColumn(2); | 
| 123 | moment = ma.getDipoleMoment(); | 
| 124 | moment *= debyeToKcal; | 
| 125 | dip = u_i * moment; | 
| 126 | trq = cross(dip, EF); | 
| 127 | //cerr << "dip = " << dip << "\n"; | 
| 128 | // cerr << "trq = " << trq << "\n"; | 
| 129 | atom->addTrq(trq); | 
| 130 | pot = -dot(dip, EF); | 
| 131 | //cerr << "pot = " << pot << "\n"; | 
| 132 | if (doParticlePot) { | 
| 133 | atom->addParticlePot(pot); | 
| 134 | } | 
| 135 | fieldPot += pot; | 
| 136 | } | 
| 137 | } | 
| 138 | } | 
| 139 | #ifdef IS_MPI | 
| 140 | MPI::COMM_WORLD.Allreduce(MPI::IN_PLACE, &fieldPot, 1, MPI::REALTYPE, | 
| 141 | MPI::SUM); | 
| 142 | #endif | 
| 143 | Snapshot* snap = info_->getSnapshotManager()->getCurrentSnapshot(); | 
| 144 | longRangePotential = snap->getLongRangePotentials(); | 
| 145 | // << "longRangePotential = " << longRangePotential << "\n"; | 
| 146 | longRangePotential[ELECTROSTATIC_FAMILY] += fieldPot; | 
| 147 | //cerr << "longRangePotential[ELECTROSTATIC_FAMILY] = " << longRangePotential[ELECTROSTATIC_FAMILY] << "\n"; | 
| 148 | snap->setLongRangePotential(longRangePotential); | 
| 149 | } | 
| 150 | } | 
| 151 |  | 
| 152 | } |