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Flexible Force Field Parameterization through Fitting on the Ab Initio-Derived Elastic Tensor.

ABSTRACT: Constructing functional forms and their corresponding force field parameters for the metal-linker interface of metal-organic frameworks is challenging. We propose fitting these parameters on the elastic tensor, computed from ab initio density functional theory calculations. The advantage of this top-down approach is that it becomes evident if functional forms are missing when components of the elastic tensor are off. As a proof-of-concept, a new flexible force field for MIL-47(V) is derived. Negative thermal expansion is observed and framework flexibility has a negligible effect on adsorption and transport properties for small guest molecules. We believe that this force field parametrization approach can serve as a useful tool for developing accurate flexible force field models that capture the correct mechanical behavior of the full periodic structure.

SUBMITTER: Heinen J

PROVIDER: S-EPMC5550891 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature

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Flexible Force Field Parameterization through Fitting on the Ab Initio-Derived Elastic Tensor.

Heinen Jurn J Burtch Nicholas C NC Walton Krista S KS Dubbeldam David D

Journal of chemical theory and computation 20170719 8

Constructing functional forms and their corresponding force field parameters for the metal-linker interface of metal-organic frameworks is challenging. We propose fitting these parameters on the elastic tensor, computed from ab initio density functional theory calculations. The advantage of this top-down approach is that it becomes evident if functional forms are missing when components of the elastic tensor are off. As a proof-of-concept, a new flexible force field for MIL-47(V) is derived. Neg ...[more]

PMID: 28661672

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