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arXiv · 1602.03174

A screened automated structural search with semiempirical methods

Yukihiro Ota·Sergi Ruiz-Barragan·Masahiko Machida·Motoyuki Shiga
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Abstract

We developed an interface program between a program suite for an automated search of chemical reaction pathways, GRRM, and a program package of semiempirical methods, MOPAC. A two-step structural search is proposed as an application of this interface program. A screening test is first performed by semiempirical calculations. Subsequently, a reoptimization procedure is done by ab initio or density functional calculations. We apply this approach to ion adsorption on cellulose. The computational efficiency is also shown for a GRRM search. The interface program is suitable for the structural search of large molecular systems for which semiempirical methods are applicable.

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Yukihiro Ota, Sergi Ruiz-Barragan, Masahiko Machida, Motoyuki Shiga. 2016-02-09. A screened automated structural search with semiempirical methods. https://doi.org/10.1016/j.cplett.2016.02.013

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