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Comparing trunk/src/primitives/GhostTorsion.cpp (file contents):
Revision 1309 by gezelter, Tue Oct 21 18:23:31 2008 UTC vs.
Revision 1953 by gezelter, Thu Dec 5 18:19:26 2013 UTC

# Line 6 | Line 6
6   * redistribute this software in source and binary code form, provided
7   * that the following conditions are met:
8   *
9 < * 1. Acknowledgement of the program authors must be made in any
10 < *    publication of scientific results based in part on use of the
11 < *    program.  An acceptable form of acknowledgement is citation of
12 < *    the article in which the program was described (Matthew
13 < *    A. Meineke, Charles F. Vardeman II, Teng Lin, Christopher
14 < *    J. Fennell and J. Daniel Gezelter, "OOPSE: An Object-Oriented
15 < *    Parallel Simulation Engine for Molecular Dynamics,"
16 < *    J. Comput. Chem. 26, pp. 252-271 (2005))
17 < *
18 < * 2. Redistributions of source code must retain the above copyright
9 > * 1. Redistributions of source code must retain the above copyright
10   *    notice, this list of conditions and the following disclaimer.
11   *
12 < * 3. Redistributions in binary form must reproduce the above copyright
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.
# Line 37 | Line 28
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 "config.h"
44 + #include <cmath>
45 +
46   #include "primitives/GhostTorsion.hpp"
47  
48 < namespace oopse {
48 > namespace OpenMD {
49    
50    GhostTorsion::GhostTorsion(Atom *atom1, Atom *atom2,  
51                               DirectionalAtom* ghostAtom, TorsionType *tt)
52      : Torsion(atom1, atom2, ghostAtom, ghostAtom, tt) {}
53    
54 <  void GhostTorsion::calcForce(RealType& angle) {
55 <    DirectionalAtom* ghostAtom = static_cast<DirectionalAtom*>(atom3_);    
54 >  void GhostTorsion::calcForce(RealType& angle, bool doParticlePot) {
55 >    DirectionalAtom* ghostAtom = static_cast<DirectionalAtom*>(atoms_[2]);    
56      
57 <    Vector3d pos1 = atom1_->getPos();
58 <    Vector3d pos2 = atom2_->getPos();
57 >    Vector3d pos1 = atoms_[0]->getPos();
58 >    Vector3d pos2 = atoms_[1]->getPos();
59      Vector3d pos3 = ghostAtom->getPos();
60      
61      Vector3d r21 = pos1 - pos2;
62      Vector3d r32 = pos2 - pos3;
63 <    Vector3d r43 = ghostAtom->getElectroFrame().getColumn(2);
63 >    Vector3d r43 = ghostAtom->getA().transpose().getColumn(2);
64      
65      //  Calculate the cross products and distances
66      Vector3d A = cross(r21, r32);
67      RealType rA = A.length();
68      Vector3d B = cross(r32, r43);
69      RealType rB = B.length();
70 <    Vector3d C = cross(r32, A);
71 <    RealType rC = C.length();
70 >
71 >    /*
72 >       If either of the two cross product vectors is tiny, that means
73 >       the three atoms involved are colinear, and the torsion angle is
74 >       going to be undefined.  The easiest check for this problem is
75 >       to use the product of the two lengths.
76 >    */
77 >    if (rA * rB < OpenMD::epsilon) return;
78      
79      A.normalize();
80      B.normalize();
71    C.normalize();
81      
82      //  Calculate the sin and cos
83      RealType cos_phi = dot(A, B) ;
# Line 83 | Line 92 | namespace oopse {
92      Vector3d f2 = dVdcosPhi * ( cross(r43, dcosdB) - cross(r21, dcosdA));
93      Vector3d f3 = dVdcosPhi * cross(dcosdB, r32);
94      
95 <    atom1_->addFrc(f1);
96 <    atom2_->addFrc(f2 - f1);
95 >    atoms_[0]->addFrc(f1);
96 >    atoms_[1]->addFrc(f2 - f1);
97      
98      ghostAtom->addFrc(-f2);
99      
100      f3.negate();
101      ghostAtom->addTrq(cross(r43, f3));    
102      
103 <    atom1_->addParticlePot(potential_);
104 <    atom2_->addParticlePot(potential_);
105 <    ghostAtom->addParticlePot(potential_);
103 >    if (doParticlePot) {
104 >      atoms_[0]->addParticlePot(potential_);
105 >      atoms_[1]->addParticlePot(potential_);
106 >      ghostAtom->addParticlePot(potential_);
107 >    }
108  
109      angle = acos(cos_phi) /M_PI * 180.0;
110    }

Comparing trunk/src/primitives/GhostTorsion.cpp (property svn:keywords):
Revision 1309 by gezelter, Tue Oct 21 18:23:31 2008 UTC vs.
Revision 1953 by gezelter, Thu Dec 5 18:19:26 2013 UTC

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