Approximation Properties and Limits of the Quantum-Classical Molecular Dynamics Model
Please always quote using this URN: urn:nbn:de:0297-zib-3102
- In molecular dynamics applications there is a growing interest in including quantum effects for simulations of larger molecules. This paper is concerned with {\em mixed quantum-classical} models which are currently discussed: the so-called QCMD model with variants and the time-dependent Born-Oppenheimer approximation. All these models are known to approximate the full quantum dynamical evolution---under different assumptions, however. We review the meaning of these assumptions and the scope of the approximation. In particular, we characterize those typical problematic situations where a mixed model might largely deviate from the full quantum evolution. One such situation of specific interest, a non-adiabatic excitation at certain energy level crossings, can promisingly be dealt with by a modification of the QCMD model that we suggest.
Author: | Christof Schütte, Folkmar A. Bornemann |
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Document Type: | ZIB-Report |
Date of first Publication: | 1997/09/25 |
Series (Serial Number): | ZIB-Report (SC-97-41) |
ZIB-Reportnumber: | SC-97-41 |
Published in: | Appeared in: P. Deuflhard, J. Hermans et al., Computational Molecular Dynamics: Challenges, Methods, Ideas., 4, Lecture Notes in Computational Science and Engineering, Springer, 380-395, 1998 |