Modified potential energy functions for constrained molecular dynamics
Please always quote using this URN: urn:nbn:de:0297-zib-3189
- In molecular dynamics the highly oscillatory vibrations in the chemical bonds are often replaced by holonomic constraints that freeze the bond length/angle to its equilibrium value. In some cases this approach can be justified if the force constants of the bond vibrations are sufficiently large. However, for moderate values of the force constant, the constrained system might lead to a dynamical behavior that is too ``rigid'' compared to the flexible model. To compensate for this effect, the concept of soft constraints was introduced [Reich 1997, Reich 1995, Reich 1996]. However, its implementation is rather expensive. In this paper, we suggest an alternative approach that modifies the force field instead of the constraint functions. This leads to a more efficient method that avoids the resonance induced instabilities of multiple-time-stepping [Bishop 1996] and the above described effect of standard constrained dynamics.
Author: | Sebastian Reich |
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Document Type: | ZIB-Report |
Date of first Publication: | 1997/11/05 |
Series (Serial Number): | ZIB-Report (SC-97-49) |
ZIB-Reportnumber: | SC-97-49 |
Published in: | Appeared in: Numerical Algorithms 19 (1998) 213-221 |