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/* |
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* Copyright (c) 2012 The University of Notre Dame. All Rights Reserved. |
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* |
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* The University of Notre Dame grants you ("Licensee") a |
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* non-exclusive, royalty free, license to use, modify and |
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* redistribute this software in source and binary code form, provided |
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* that the following conditions are met: |
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* |
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* 1. Redistributions of source code must retain the above copyright |
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* notice, this list of conditions and the following disclaimer. |
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* |
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* 2. Redistributions in binary form must reproduce the above copyright |
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* notice, this list of conditions and the following disclaimer in the |
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* documentation and/or other materials provided with the |
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* distribution. |
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* |
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* This software is provided "AS IS," without a warranty of any |
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* kind. All express or implied conditions, representations and |
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* warranties, including any implied warranty of merchantability, |
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* fitness for a particular purpose or non-infringement, are hereby |
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* excluded. The University of Notre Dame and its licensors shall not |
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* be liable for any damages suffered by licensee as a result of |
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* using, modifying or distributing the software or its |
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* derivatives. In no event will the University of Notre Dame or its |
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* licensors be liable for any lost revenue, profit or data, or for |
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* direct, indirect, special, consequential, incidental or punitive |
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* damages, however caused and regardless of the theory of liability, |
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* arising out of the use of or inability to use software, even if the |
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* University of Notre Dame has been advised of the possibility of |
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* such damages. |
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* |
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* SUPPORT OPEN SCIENCE! If you use OpenMD or its source code in your |
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* research, please cite the appropriate papers when you publish your |
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* work. Good starting points are: |
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* |
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* [1] Meineke, et al., J. Comp. Chem. 26, 252-271 (2005). |
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* [2] Fennell & Gezelter, J. Chem. Phys. 124, 234104 (2006). |
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* [3] Sun, Lin & Gezelter, J. Chem. Phys. 128, 234107 (2008). |
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* [4] Kuang & Gezelter, J. Chem. Phys. 133, 164101 (2010). |
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* [5] Vardeman, Stocker & Gezelter, J. Chem. Theory Comput. 7, 834 (2011). |
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*/ |
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|
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#ifdef IS_MPI |
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#include <mpi.h> |
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#endif |
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|
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#include "flucq/FluctuatingChargeForces.hpp" |
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#include "types/FluctuatingChargeAdapter.hpp" |
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|
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namespace OpenMD { |
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|
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FluctuatingChargeForces::FluctuatingChargeForces(SimInfo* info) : |
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info_(info), initialized_(false) { |
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} |
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|
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void FluctuatingChargeForces::initialize(){ |
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FQtypes.clear(); |
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FQtids.clear(); |
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FQtids.resize( forceField_->getNAtomType(), -1); |
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|
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set<AtomType*>::iterator at; |
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for (at = simTypes_.begin(); at != simTypes_.end(); ++at) |
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if ((*at)->isFluctuatingCharge()) addType(*at); |
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|
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initialized_ = true; |
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} |
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|
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void FluctuatingChargeForces::getSelfInteraction(int atid, RealType charge, |
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RealType &potential, |
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RealType &force) { |
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if (!initialized_) initialize(); |
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|
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data = FQMap[FQtids[atid]]; |
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|
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if (data.hasMultipleMinima) { |
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int nDiabats = data.diabaticStates.size(); |
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if (nDiabats == 2){ |
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RealType q1 = data.diabaticStates[0].first; |
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RealType e1 = data.diabaticStates[0].second; |
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RealType q2 = data.diabaticStates[1].first; |
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RealType e2 = data.diabaticStates[1].second; |
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RealType k = data.curvature; |
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RealType c = data.coupling; |
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|
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RealType v1 = e1 + 0.5 * k * (charge-q1)*(charge-q1); |
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RealType v1p = k*(charge-q1); |
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RealType v2 = e2 + 0.5 * k * (charge-q2)*(charge-q2); |
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RealType v2p = k*(charge-q2); |
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potential += (v1 + v2 - sqrt(4*c*c+ v1*v1 - 2.0*v1*v2 + v2*v2))/2.0; |
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force -= (v1p + v2p - ((v1 - v2) * (v1p - v2p)) / |
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sqrt(4*c*c + v1*v1 - 2*v1*v2 + v2*v2))/2.0; |
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} else { |
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std::cerr << "too many diabatic states\n"; |
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} |
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} else { |
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RealType Jii = data.hardness; |
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RealType chi = data.electronegativity; |
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force -= charge * Jii + chi; |
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potential += charge * (charge * Jii * 0.5 + chi); |
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} |
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return; |
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} |
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|
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void FluctuatingChargeForces::addType(AtomType* atomType) { |
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FluctuatingChargeAtomData data; |
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FluctuatingChargeAdapter fqa = FluctuatingChargeAdapter(atomType); |
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if (fqa.isFluctuatingCharge()) { |
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if (fqa.hasMultipleMinima()) { |
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data.hasMultipleMinima = true; |
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data.curvature = fqa.getCurvature(); |
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data.coupling = fqa.getCoupling(); |
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data.diabaticStates = fqa.getDiabaticStates(); |
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} else { |
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data.hasMultipleMinima = false; |
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data.electronegativity = fqa.getElectronegativity(); |
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data.hardness = fqa.getHardness(); |
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data.slaterN = fqa.getSlaterN(); |
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data.slaterZeta = fqa.getSlaterZeta(); |
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} |
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int atid = atomType->getIdent(); |
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int fqtid = FQtypes.size(); |
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|
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pair<set<int>::iterator,bool> ret; |
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ret = FQtypes.insert( atid ); |
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if (ret.second == false) { |
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sprintf( painCave.errMsg, |
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"FluctuatingChargeForces already had a previous fluctuating " |
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"charge entry with ident %d\n", |
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atid ); |
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painCave.severity = OPENMD_INFO; |
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painCave.isFatal = 0; |
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simError(); |
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} |
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FQtids[atid] = fqtid; |
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FQMap.push_back(data); |
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} |
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} |
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} |
