Born-Oppenheimer Molecular Dynamics in ONETEP
Simon Dubois2016
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Abstract
The MD functionality implemented in ONETEP is founded on the Born-Oppenheimer approximation which states that the electrons are much lighter than nuclei, the dynamics of electrons is much faster compared to the dynamics of the nuclei. As a consequence, the former can be considered to react instantaneously to the motion of the latter. The forces acting on the nuclei are derived from the ground state electronic configuration by means of the Hellmann-Feynamn theorem. The motion of the nuclei is described by the laws of classical mechanics
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