摘要：Current minimisation strategies for atomistic or force field based methods generally rely upon transforming the internalcoordinates into a Cartesian framework and optimising the atomic positions subject to restraining forces generatedby the force field. This is inefficient, especially when the potential energy hypersurface (PEHS) is complex withmultiple minima. Prediction of the global minimum is therefore uncertain. This paper describes the initial stages ofthe development of a novel empirical approach, using differentiation of the potential energy functions to identify allstationary points on the PEHS. Evaluation of the potential energy at each stationary point allows the identificationof the global minimum. Suitable examples are used to demonstrate the applicability of the approach, with resultsin complete agreement with those obtained using standard molecular mechanics algorithms. Indeed, the calculationis significantly shorter, and can be calculated on paper for simple systems. Systems containing 1,4- non-bondedinteractions, described using 6-12 Lennard Jones potentials, produce a polynomial of degree 14, which is difficult tosolve analytically. Further work on this aspect and the inclusion of torsional terms is underway.
关键词：Potential energy surfaces ; Symbolic computation (computer algebra)
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