src/nonbonded/SC.cpp

/*
 * Copyright (c) 2005 The University of Notre Dame. All Rights Reserved.
 *
 * The University of Notre Dame grants you ("Licensee") a
 * non-exclusive, royalty free, license to use, modify and
 * redistribute this software in source and binary code form, provided
 * that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the
 *    distribution.
 *
 * This software is provided "AS IS," without a warranty of any
 * kind. All express or implied conditions, representations and
 * warranties, including any implied warranty of merchantability,
 * fitness for a particular purpose or non-infringement, are hereby
 * excluded.  The University of Notre Dame and its licensors shall not
 * be liable for any damages suffered by licensee as a result of
 * using, modifying or distributing the software or its
 * derivatives. In no event will the University of Notre Dame or its
 * licensors be liable for any lost revenue, profit or data, or for
 * direct, indirect, special, consequential, incidental or punitive
 * damages, however caused and regardless of the theory of liability,
 * arising out of the use of or inability to use software, even if the
 * University of Notre Dame has been advised of the possibility of
 * such damages.
 *
 * SUPPORT OPEN SCIENCE!  If you use OpenMD or its source code in your
 * research, please cite the appropriate papers when you publish your
 * work.  Good starting points are:
 *                                                                      
 * [1]  Meineke, et al., J. Comp. Chem. 26, 252-271 (2005).             
 * [2]  Fennell & Gezelter, J. Chem. Phys. 124, 234104 (2006).          
 * [3]  Sun, Lin & Gezelter, J. Chem. Phys. 128, 24107 (2008).          
 * [4]  Vardeman & Gezelter, in progress (2009).                        
 */

#include <stdio.h>
#include <string.h>

#include <cmath>
#include "nonbonded/SC.hpp"
#include "utils/simError.h"
#include "types/NonBondedInteractionType.hpp"

namespace OpenMD {


  SC::SC() : name_("SC"), initialized_(false), forceField_(NULL), 
             scRcut_(0.0), np_(3000) {}
  
  SCParam SC::getSCParam(AtomType* atomType) {
    
    // Do sanity checking on the AtomType we were passed before
    // building any data structures:
    if (!atomType->isSC()) {
      sprintf( painCave.errMsg,
               "SC::getSCParam was passed an atomType (%s) that does not\n"
               "\tappear to be a Sutton-Chen (SC) atom.\n",
               atomType->getName().c_str());
      painCave.severity = OPENMD_ERROR;
      painCave.isFatal = 1;
      simError();
    }
    
    GenericData* data = atomType->getPropertyByName("SC");
    if (data == NULL) {
      sprintf( painCave.errMsg, "SC::getSCParam could not find SC\n"
               "\tparameters for atomType %s.\n", 
               atomType->getName().c_str());
      painCave.severity = OPENMD_ERROR;
      painCave.isFatal = 1;
      simError(); 
    }
    
    SCParamGenericData* scData = dynamic_cast<SCParamGenericData*>(data);
    if (scData == NULL) {
      sprintf( painCave.errMsg,
               "SC::getSCParam could not convert GenericData to SCParamGenericData\n"
               "\tfor atom type %s\n", atomType->getName().c_str());
      painCave.severity = OPENMD_ERROR;
      painCave.isFatal = 1;
      simError();          
    }
    
    return scData->getData();
  }

  RealType SC::getC(AtomType* atomType) {    
    SCParam scParam = getSCParam(atomType);
    return scParam.c;
  }

  RealType SC::getM(AtomType* atomType) {    
    SCParam scParam = getSCParam(atomType);
    return scParam.m;
  }

  RealType SC::getM(AtomType* atomType1, AtomType* atomType2) {    
    RealType m1 = getM(atomType1);
    RealType m2 = getM(atomType2);
    return 0.5 * (m1 + m2);
  }

  RealType SC::getN(AtomType* atomType) {    
    SCParam scParam = getSCParam(atomType);
    return scParam.n;
  }

  RealType SC::getN(AtomType* atomType1, AtomType* atomType2) {    
    RealType n1 = getN(atomType1);
    RealType n2 = getN(atomType2);
    return 0.5 * (n1 + n2);
  }

  RealType SC::getAlpha(AtomType* atomType) {    
    SCParam scParam = getSCParam(atomType);
    return scParam.alpha;
  }

  RealType SC::getAlpha(AtomType* atomType1, AtomType* atomType2) {    
    RealType alpha1 = getAlpha(atomType1);
    RealType alpha2 = getAlpha(atomType2);

    ForceFieldOptions& fopts = forceField_->getForceFieldOptions();
    std::string DistanceMix = fopts.getDistanceMixingRule();
    toUpper(DistanceMix);

    if (DistanceMix == "GEOMETRIC") 
      return sqrt(alpha1 * alpha2);
    else 
      return 0.5 * (alpha1 + alpha2);
  }

  RealType SC::getEpsilon(AtomType* atomType) {    
    SCParam scParam = getSCParam(atomType);
    return scParam.epsilon;
  }

  RealType SC::getEpsilon(AtomType* atomType1, AtomType* atomType2) {    
    RealType epsilon1 = getEpsilon(atomType1);
    RealType epsilon2 = getEpsilon(atomType2);
    return sqrt(epsilon1 * epsilon2);
  }

  void SC::initialize() { 
    // find all of the SC atom Types:
    ForceField::AtomTypeContainer* atomTypes = forceField_->getAtomTypes();
    ForceField::AtomTypeContainer::MapTypeIterator i;
    AtomType* at;

    for (at = atomTypes->beginType(i); at != NULL; 
         at = atomTypes->nextType(i)) {
      if (at->isSC())
        addType(at);
    }    
    initialized_ = true;
  }
  
  
  void SC::addType(AtomType* atomType){

    SCAtomData scAtomData;
    
    scAtomData.c = getC(atomType);
    scAtomData.m = getM(atomType);
    scAtomData.n = getN(atomType);
    scAtomData.alpha = getAlpha(atomType);
    scAtomData.epsilon = getEpsilon(atomType);
    scAtomData.rCut = 2.0 * scAtomData.alpha;

    // add it to the map:
    AtomTypeProperties atp = atomType->getATP();    

    pair<map<int,AtomType*>::iterator,bool> ret;    
    ret = SClist.insert( pair<int, AtomType*>(atp.ident, atomType) );
    if (ret.second == false) {
      sprintf( painCave.errMsg,
               "SC already had a previous entry with ident %d\n",
               atp.ident);
      painCave.severity = OPENMD_INFO;
      painCave.isFatal = 0;
      simError();         
    }

    SCMap[atomType] = scAtomData;
    
    // Now, iterate over all known types and add to the mixing map:
    
    map<AtomType*, SCAtomData>::iterator it;
    for( it = SCMap.begin(); it != SCMap.end(); ++it) {
      
      AtomType* atype2 = (*it).first;
      
      SCInteractionData mixer;

      mixer.alpha = getAlpha(atomType, atype2);
      mixer.rCut = 2.0 * mixer.alpha;
      mixer.epsilon = getEpsilon(atomType, atype2);
      mixer.m = getM(atomType, atype2);
      mixer.n = getN(atomType, atype2);

      RealType dr = mixer.rCut / (np_ - 1);
      vector<RealType> rvals;
      vector<RealType> vvals;
      vector<RealType> phivals;
    
      rvals.push_back(0.0);
      vvals.push_back(0.0);
      phivals.push_back(0.0);

      for (int k = 1; k < np_; k++) {
        RealType r = dr * k;
        rvals.push_back(r);
        vvals.push_back( mixer.epsilon * pow(mixer.alpha/r, mixer.n) );
        phivals.push_back( pow(mixer.alpha/r, mixer.m) );
      }

      mixer.vCut = mixer.epsilon * pow(mixer.alpha/mixer.rCut, mixer.n);
    
      CubicSpline* V = new CubicSpline();
      V->addPoints(rvals, vvals);
      
      CubicSpline* phi = new CubicSpline();
      phi->addPoints(rvals, phivals);
      
      mixer.V = V;
      mixer.phi = phi;

      mixer.explicitlySet = false;

      pair<AtomType*, AtomType*> key1, key2;
      key1 = make_pair(atomType, atype2);
      key2 = make_pair(atype2, atomType);
      
      MixingMap[key1] = mixer;
      if (key2 != key1) {
        MixingMap[key2] = mixer;
      }
    }      
    return;
  }
  
  void SC::addExplicitInteraction(AtomType* atype1, AtomType* atype2, 
                                  RealType epsilon, RealType m, RealType n,
                                  RealType alpha) {
    
    // in case these weren't already in the map
    addType(atype1);
    addType(atype2);

    SCInteractionData mixer;

    mixer.epsilon = epsilon;
    mixer.m = m;
    mixer.n = n;
    mixer.alpha = alpha;
    mixer.rCut = 2.0 * mixer.alpha;
    
    RealType dr = mixer.rCut / (np_ - 1);
    vector<RealType> rvals;
    vector<RealType> vvals;
    vector<RealType> phivals;
    
    rvals.push_back(0.0);
    vvals.push_back(0.0);
    phivals.push_back(0.0);
    
    for (int k = 1; k < np_; k++) {
      RealType r = dr * k;
      rvals.push_back(r);
      vvals.push_back( mixer.epsilon * pow(mixer.alpha/r, mixer.n) );
      phivals.push_back( pow(mixer.alpha/r, mixer.m) );
    }
    
    mixer.vCut = mixer.epsilon * pow(mixer.alpha/mixer.rCut, mixer.n);
    
    CubicSpline* V = new CubicSpline();
    V->addPoints(rvals, vvals);
    
    CubicSpline* phi = new CubicSpline();
    phi->addPoints(rvals, phivals);
    
    mixer.V = V;
    mixer.phi = phi;
    
    mixer.explicitlySet = true;

    pair<AtomType*, AtomType*> key1, key2;
    key1 = make_pair(atype1, atype2);
    key2 = make_pair(atype2, atype1);
    
    MixingMap[key1] = mixer;
    if (key2 != key1) {
      MixingMap[key2] = mixer;
    }    
    return;
  }

  void SC::calcDensity(DensityData ddat) {
    
    if (!initialized_) initialize();
    
    SCInteractionData mixer = MixingMap[make_pair(ddat.atype1, ddat.atype2)];

    RealType rcij = mixer.rCut;

    if (ddat.rij < rcij) {
      ddat.rho_i_at_j = mixer.phi->getValueAt(ddat.rij);
      ddat.rho_j_at_i = ddat.rho_i_at_j;
    } else {
      ddat.rho_i_at_j = 0.0;
      ddat.rho_j_at_i = 0.0;
    }

    return;
  }

  void SC::calcFunctional(FunctionalData fdat) {

    if (!initialized_) initialize();

    SCAtomData data1 = SCMap[fdat.atype];
    
    fdat.frho = - data1.c * data1.epsilon * sqrt(fdat.rho);
    fdat.dfrhodrho = 0.5 * fdat.frho / fdat.rho;
    
    return;
  }
  
 
  void SC::calcForce(InteractionData idat) {
    
    if (!initialized_) initialize();
    
    SCAtomData data1 = SCMap[idat.atype1];
    SCAtomData data2 = SCMap[idat.atype2];

    SCInteractionData mixer = MixingMap[make_pair(idat.atype1, idat.atype2)];

    RealType rcij = mixer.rCut;

    if (idat.rij < rcij) {
      RealType vcij = mixer.vCut;
      
      pair<RealType, RealType> res;
      
      res = mixer.phi->getValueAndDerivativeAt(idat.rij);
      RealType rhtmp = res.first;
      RealType drhodr = res.second;
      
      res = mixer.V->getValueAndDerivativeAt(idat.rij);
      RealType vptmp = res.first;
      RealType dvpdr = res.second;
      
      RealType pot_temp = vptmp - vcij;
      idat.vpair += pot_temp;
      
      RealType dudr = drhodr * (idat.dfrho1 + idat.dfrho2) + dvpdr;
      
      idat.f1 += idat.d * dudr / idat.rij;
        
      // particle_pot is the difference between the full potential 
      // and the full potential without the presence of a particular
      // particle (atom1).
      //
      // This reduces the density at other particle locations, so
      // we need to recompute the density at atom2 assuming atom1
      // didn't contribute.  This then requires recomputing the
      // density functional for atom2 as well.
      //
      // Most of the particle_pot heavy lifting comes from the
      // pair interaction, and will be handled by vpair.
      
      idat.fshift1 = - data1.c * data1.epsilon * sqrt(idat.rho1 - rhtmp);
      idat.fshift2 = - data2.c * data2.epsilon * sqrt(idat.rho2 - rhtmp);
      
      idat.pot += pot_temp;
    }
      
    return;    
  }

  RealType SC::getSuggestedCutoffRadius(AtomType* at1, AtomType* at2) {
    if (!initialized_) initialize();   
    pair<AtomType*, AtomType*> key = make_pair(at1, at2); 
    map<pair<AtomType*, AtomType*>, SCInteractionData>::iterator it;
    it = MixingMap.find(key);
    if (it == MixingMap.end()) 
      return 0.0;
    else  {
      SCInteractionData mixer = (*it).second;
      return mixer.rCut;
    }
  }
}
Revision:	1505
Committed:	Sun Oct 3 22:18:59 2010 UTC (14 years, 6 months ago) by gezelter
File size:	12209 byte(s)
Log Message:	Less busted than it was on last check-in, but still won't completely build.
#	Content
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] Vardeman & Gezelter, in progress (2009).
40	*/
41
42	#include <stdio.h>
43	#include <string.h>
44
45	#include <cmath>
46	#include "nonbonded/SC.hpp"
47	#include "utils/simError.h"
48	#include "types/NonBondedInteractionType.hpp"
49
50	namespace OpenMD {
51
52
53	SC::SC() : name_("SC"), initialized_(false), forceField_(NULL),
54	scRcut_(0.0), np_(3000) {}
55
56	SCParam SC::getSCParam(AtomType* atomType) {
57
58	// Do sanity checking on the AtomType we were passed before
59	// building any data structures:
60	if (!atomType->isSC()) {
61	sprintf( painCave.errMsg,
62	"SC::getSCParam was passed an atomType (%s) that does not\n"
63	"\tappear to be a Sutton-Chen (SC) atom.\n",
64	atomType->getName().c_str());
65	painCave.severity = OPENMD_ERROR;
66	painCave.isFatal = 1;
67	simError();
68	}
69
70	GenericData* data = atomType->getPropertyByName("SC");
71	if (data == NULL) {
72	sprintf( painCave.errMsg, "SC::getSCParam could not find SC\n"
73	"\tparameters for atomType %s.\n",
74	atomType->getName().c_str());
75	painCave.severity = OPENMD_ERROR;
76	painCave.isFatal = 1;
77	simError();
78	}
79
80	SCParamGenericData* scData = dynamic_cast<SCParamGenericData*>(data);
81	if (scData == NULL) {
82	sprintf( painCave.errMsg,
83	"SC::getSCParam could not convert GenericData to SCParamGenericData\n"
84	"\tfor atom type %s\n", atomType->getName().c_str());
85	painCave.severity = OPENMD_ERROR;
86	painCave.isFatal = 1;
87	simError();
88	}
89
90	return scData->getData();
91	}
92
93	RealType SC::getC(AtomType* atomType) {
94	SCParam scParam = getSCParam(atomType);
95	return scParam.c;
96	}
97
98	RealType SC::getM(AtomType* atomType) {
99	SCParam scParam = getSCParam(atomType);
100	return scParam.m;
101	}
102
103	RealType SC::getM(AtomType* atomType1, AtomType* atomType2) {
104	RealType m1 = getM(atomType1);
105	RealType m2 = getM(atomType2);
106	return 0.5 * (m1 + m2);
107	}
108
109	RealType SC::getN(AtomType* atomType) {
110	SCParam scParam = getSCParam(atomType);
111	return scParam.n;
112	}
113
114	RealType SC::getN(AtomType* atomType1, AtomType* atomType2) {
115	RealType n1 = getN(atomType1);
116	RealType n2 = getN(atomType2);
117	return 0.5 * (n1 + n2);
118	}
119
120	RealType SC::getAlpha(AtomType* atomType) {
121	SCParam scParam = getSCParam(atomType);
122	return scParam.alpha;
123	}
124
125	RealType SC::getAlpha(AtomType* atomType1, AtomType* atomType2) {
126	RealType alpha1 = getAlpha(atomType1);
127	RealType alpha2 = getAlpha(atomType2);
128
129	ForceFieldOptions& fopts = forceField_->getForceFieldOptions();
130	std::string DistanceMix = fopts.getDistanceMixingRule();
131	toUpper(DistanceMix);
132
133	if (DistanceMix == "GEOMETRIC")
134	return sqrt(alpha1 * alpha2);
135	else
136	return 0.5 * (alpha1 + alpha2);
137	}
138
139	RealType SC::getEpsilon(AtomType* atomType) {
140	SCParam scParam = getSCParam(atomType);
141	return scParam.epsilon;
142	}
143
144	RealType SC::getEpsilon(AtomType* atomType1, AtomType* atomType2) {
145	RealType epsilon1 = getEpsilon(atomType1);
146	RealType epsilon2 = getEpsilon(atomType2);
147	return sqrt(epsilon1 * epsilon2);
148	}
149
150	void SC::initialize() {
151	// find all of the SC atom Types:
152	ForceField::AtomTypeContainer* atomTypes = forceField_->getAtomTypes();
153	ForceField::AtomTypeContainer::MapTypeIterator i;
154	AtomType* at;
155
156	for (at = atomTypes->beginType(i); at != NULL;
157	at = atomTypes->nextType(i)) {
158	if (at->isSC())
159	addType(at);
160	}
161	initialized_ = true;
162	}
163
164
165
166	void SC::addType(AtomType* atomType){
167
168	SCAtomData scAtomData;
169
170	scAtomData.c = getC(atomType);
171	scAtomData.m = getM(atomType);
172	scAtomData.n = getN(atomType);
173	scAtomData.alpha = getAlpha(atomType);
174	scAtomData.epsilon = getEpsilon(atomType);
175	scAtomData.rCut = 2.0 * scAtomData.alpha;
176
177	// add it to the map:
178	AtomTypeProperties atp = atomType->getATP();
179
180	pair<map<int,AtomType*>::iterator,bool> ret;
181	ret = SClist.insert( pair<int, AtomType*>(atp.ident, atomType) );
182	if (ret.second == false) {
183	sprintf( painCave.errMsg,
184	"SC already had a previous entry with ident %d\n",
185	atp.ident);
186	painCave.severity = OPENMD_INFO;
187	painCave.isFatal = 0;
188	simError();
189	}
190
191	SCMap[atomType] = scAtomData;
192
193	// Now, iterate over all known types and add to the mixing map:
194
195	map<AtomType*, SCAtomData>::iterator it;
196	for( it = SCMap.begin(); it != SCMap.end(); ++it) {
197
198	AtomType* atype2 = (*it).first;
199
200	SCInteractionData mixer;
201
202	mixer.alpha = getAlpha(atomType, atype2);
203	mixer.rCut = 2.0 * mixer.alpha;
204	mixer.epsilon = getEpsilon(atomType, atype2);
205	mixer.m = getM(atomType, atype2);
206	mixer.n = getN(atomType, atype2);
207
208	RealType dr = mixer.rCut / (np_ - 1);
209	vector<RealType> rvals;
210	vector<RealType> vvals;
211	vector<RealType> phivals;
212
213	rvals.push_back(0.0);
214	vvals.push_back(0.0);
215	phivals.push_back(0.0);
216
217	for (int k = 1; k < np_; k++) {
218	RealType r = dr * k;
219	rvals.push_back(r);
220	vvals.push_back( mixer.epsilon * pow(mixer.alpha/r, mixer.n) );
221	phivals.push_back( pow(mixer.alpha/r, mixer.m) );
222	}
223
224	mixer.vCut = mixer.epsilon * pow(mixer.alpha/mixer.rCut, mixer.n);
225
226	CubicSpline* V = new CubicSpline();
227	V->addPoints(rvals, vvals);
228
229	CubicSpline* phi = new CubicSpline();
230	phi->addPoints(rvals, phivals);
231
232	mixer.V = V;
233	mixer.phi = phi;
234
235	mixer.explicitlySet = false;
236
237	pair<AtomType, AtomType> key1, key2;
238	key1 = make_pair(atomType, atype2);
239	key2 = make_pair(atype2, atomType);
240
241	MixingMap[key1] = mixer;
242	if (key2 != key1) {
243	MixingMap[key2] = mixer;
244	}
245	}
246	return;
247	}
248
249	void SC::addExplicitInteraction(AtomType* atype1, AtomType* atype2,
250	RealType epsilon, RealType m, RealType n,
251	RealType alpha) {
252
253	// in case these weren't already in the map
254	addType(atype1);
255	addType(atype2);
256
257	SCInteractionData mixer;
258
259	mixer.epsilon = epsilon;
260	mixer.m = m;
261	mixer.n = n;
262	mixer.alpha = alpha;
263	mixer.rCut = 2.0 * mixer.alpha;
264
265	RealType dr = mixer.rCut / (np_ - 1);
266	vector<RealType> rvals;
267	vector<RealType> vvals;
268	vector<RealType> phivals;
269
270	rvals.push_back(0.0);
271	vvals.push_back(0.0);
272	phivals.push_back(0.0);
273
274	for (int k = 1; k < np_; k++) {
275	RealType r = dr * k;
276	rvals.push_back(r);
277	vvals.push_back( mixer.epsilon * pow(mixer.alpha/r, mixer.n) );
278	phivals.push_back( pow(mixer.alpha/r, mixer.m) );
279	}
280
281	mixer.vCut = mixer.epsilon * pow(mixer.alpha/mixer.rCut, mixer.n);
282
283	CubicSpline* V = new CubicSpline();
284	V->addPoints(rvals, vvals);
285
286	CubicSpline* phi = new CubicSpline();
287	phi->addPoints(rvals, phivals);
288
289	mixer.V = V;
290	mixer.phi = phi;
291
292	mixer.explicitlySet = true;
293
294	pair<AtomType, AtomType> key1, key2;
295	key1 = make_pair(atype1, atype2);
296	key2 = make_pair(atype2, atype1);
297
298	MixingMap[key1] = mixer;
299	if (key2 != key1) {
300	MixingMap[key2] = mixer;
301	}
302	return;
303	}
304
305	void SC::calcDensity(DensityData ddat) {
306
307	if (!initialized_) initialize();
308
309	SCInteractionData mixer = MixingMap[make_pair(ddat.atype1, ddat.atype2)];
310
311	RealType rcij = mixer.rCut;
312
313	if (ddat.rij < rcij) {
314	ddat.rho_i_at_j = mixer.phi->getValueAt(ddat.rij);
315	ddat.rho_j_at_i = ddat.rho_i_at_j;
316	} else {
317	ddat.rho_i_at_j = 0.0;
318	ddat.rho_j_at_i = 0.0;
319	}
320
321	return;
322	}
323
324	void SC::calcFunctional(FunctionalData fdat) {
325
326	if (!initialized_) initialize();
327
328	SCAtomData data1 = SCMap[fdat.atype];
329
330	fdat.frho = - data1.c * data1.epsilon * sqrt(fdat.rho);
331	fdat.dfrhodrho = 0.5 * fdat.frho / fdat.rho;
332
333	return;
334	}
335
336
337	void SC::calcForce(InteractionData idat) {
338
339	if (!initialized_) initialize();
340
341	SCAtomData data1 = SCMap[idat.atype1];
342	SCAtomData data2 = SCMap[idat.atype2];
343
344	SCInteractionData mixer = MixingMap[make_pair(idat.atype1, idat.atype2)];
345
346	RealType rcij = mixer.rCut;
347
348	if (idat.rij < rcij) {
349	RealType vcij = mixer.vCut;
350
351	pair<RealType, RealType> res;
352
353	res = mixer.phi->getValueAndDerivativeAt(idat.rij);
354	RealType rhtmp = res.first;
355	RealType drhodr = res.second;
356
357	res = mixer.V->getValueAndDerivativeAt(idat.rij);
358	RealType vptmp = res.first;
359	RealType dvpdr = res.second;
360
361	RealType pot_temp = vptmp - vcij;
362	idat.vpair += pot_temp;
363
364	RealType dudr = drhodr * (idat.dfrho1 + idat.dfrho2) + dvpdr;
365
366	idat.f1 += idat.d * dudr / idat.rij;
367
368	// particle_pot is the difference between the full potential
369	// and the full potential without the presence of a particular
370	// particle (atom1).
371	//
372	// This reduces the density at other particle locations, so
373	// we need to recompute the density at atom2 assuming atom1
374	// didn't contribute. This then requires recomputing the
375	// density functional for atom2 as well.
376	//
377	// Most of the particle_pot heavy lifting comes from the
378	// pair interaction, and will be handled by vpair.
379
380	idat.fshift1 = - data1.c * data1.epsilon * sqrt(idat.rho1 - rhtmp);
381	idat.fshift2 = - data2.c * data2.epsilon * sqrt(idat.rho2 - rhtmp);
382
383	idat.pot += pot_temp;
384	}
385
386	return;
387	}
388
389	RealType SC::getSuggestedCutoffRadius(AtomType* at1, AtomType* at2) {
390	if (!initialized_) initialize();
391	pair<AtomType, AtomType> key = make_pair(at1, at2);
392	map<pair<AtomType, AtomType>, SCInteractionData>::iterator it;
393	it = MixingMap.find(key);
394	if (it == MixingMap.end())
395	return 0.0;
396	else {
397	SCInteractionData mixer = (*it).second;
398	return mixer.rCut;
399	}
400	}
401	}