ViewVC Help
View File | Revision Log | Show Annotations | View Changeset | Root Listing
root/OpenMD/branches/development/src/primitives/GhostBend.cpp
(Generate patch)

Comparing:
trunk/src/primitives/GhostBend.cpp (file contents), Revision 963 by tim, Wed May 17 21:51:42 2006 UTC vs.
branches/development/src/primitives/GhostBend.cpp (file contents), Revision 1465 by chuckv, Fri Jul 9 23:08:25 2010 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, 24107 (2008).          
39 + * [4]  Vardeman & Gezelter, in progress (2009).                        
40   */
41  
42   #include "primitives/GhostBend.hpp"
43   #include "primitives/DirectionalAtom.hpp"
44 < namespace oopse {
44 > namespace OpenMD {
45  
46    /**@todo still a lot left to improve*/
47    void GhostBend::calcForce(RealType& angle) {
# Line 50 | Line 50 | namespace oopse {
50      Vector3d pos1 = atom1_->getPos();
51      Vector3d pos2 = ghostAtom->getPos();
52  
53 <    Vector3d r12 = pos1 - pos2;
54 <    RealType d12 = r12.length();
53 >    Vector3d r21 = pos1 - pos2;  
54 >    RealType d21 = r21.length();
55 >    
56 >    RealType d21inv = 1.0 / d21;
57 >  
58 >    // we need the transpose of A to get the lab fixed vector:
59 >    Vector3d r23 = ghostAtom->getA().transpose().getColumn(2);
60 >    RealType d23 = r23.length();
61 >    
62 >    RealType d23inv = 1.0 / d23;
63 >    
64 >    RealType cosTheta = dot(r21, r23) / (d21 * d23);
65  
56    RealType d12inv = 1.0 / d12;
57
58    Vector3d r32 = ghostAtom->getElectroFrame().getColumn(2);
59    RealType d32 = r32.length();
60
61    RealType d32inv = 1.0 / d32;
62
63    RealType cosTheta = dot(r12, r32) / (d12 * d32);
64
66      //check roundoff    
67      if (cosTheta > 1.0) {
68        cosTheta = 1.0;
69      } else if (cosTheta < -1.0) {
70        cosTheta = -1.0;
71      }
72 <
72 >    
73      RealType theta = acos(cosTheta);
74  
75 <    RealType firstDerivative;
76 <
77 <    bendType_->calcForce(theta, firstDerivative, potential_);
78 <
75 >    RealType dVdTheta;
76 >    
77 >    bendType_->calcForce(theta, potential_, dVdTheta);
78 >    
79      RealType sinTheta = sqrt(1.0 - cosTheta * cosTheta);
80 <
81 <    if (fabs(sinTheta) < 1.0E-12) {
82 <      sinTheta = 1.0E-12;
80 >    
81 >    if (fabs(sinTheta) < 1.0E-6) {
82 >      sinTheta = 1.0E-6;
83      }
84 +    
85 +    RealType commonFactor1 = dVdTheta / sinTheta * d21inv;
86 +    RealType commonFactor2 = dVdTheta / sinTheta * d23inv;
87 +    
88 +    Vector3d force1 = commonFactor1 * (r23 * d23inv - r21*d21inv*cosTheta);
89 +    Vector3d force3 = commonFactor2 * (r21 * d21inv - r23*d23inv*cosTheta);
90  
91 <    RealType commonFactor1 = -firstDerivative / sinTheta * d12inv;
85 <    RealType commonFactor2 = -firstDerivative / sinTheta * d32inv;
91 >    // Total force in current bend is zero
92  
87    Vector3d force1 = commonFactor1*(r12*(d12inv*cosTheta) - r32*d32inv);
88    Vector3d force3 = commonFactor2*(r32*(d32inv*cosTheta) - r12*d12inv);
93      atom1_->addFrc(force1);
94      ghostAtom->addFrc(-force1);
91    /**@todo test correctness */
92    ghostAtom->addTrq(cross(r32, force3) );
95  
96 <    angle = theta /M_PI * 180.0;
96 >    ghostAtom->addTrq( cross(r23, force3) );    
97  
98 <  }
98 >    atom1_->addParticlePot(potential_);
99 >    ghostAtom->addParticlePot(potential_);
100  
101 < } //end namespace oopse
101 >    angle = theta /M_PI * 180.0;
102 >  
103 >  }  
104 > } //end namespace OpenMD
105  

Comparing:
trunk/src/primitives/GhostBend.cpp (property svn:keywords), Revision 963 by tim, Wed May 17 21:51:42 2006 UTC vs.
branches/development/src/primitives/GhostBend.cpp (property svn:keywords), Revision 1465 by chuckv, Fri Jul 9 23:08:25 2010 UTC

# Line 0 | Line 1
1 + Author Id Revision Date

Diff Legend

Removed lines
+ Added lines
< Changed lines
> Changed lines