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arXiv · 1607.07285

A general forcefield for accurate phonon properties of metal-organic frameworks

J. K. Bristow·J. M. Skelton·K. L. Svane·A. Walsh·J. D. Gale
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Abstract

We report the development of a forcefield capable of reproducing accurate lattice dynamics of metal-organic frameworks. Phonon spectra, thermodynamic and mechanical properties, such as free energies, heat capacities and bulk moduli, are calculated using the quasi-harmonic approximation to account for anharmonic behaviour due to thermal expansion. Comparison to density functional theory calculations of properties such as Gr$\mathrm{\ddot{u}}$neisen parameters, bulk moduli and thermal expansion supports the accuracy of the derived forcefield model. Material properties are also reported in a full analysis of the lattice dynamics of an initial subset of structures including: MOF-5, IRMOF-10, UiO-66, UiO-67, NOTT-300, MIL-125, MOF-74 and MOF-650.

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J. K. Bristow, J. M. Skelton, K. L. Svane, A. Walsh, J. D. Gale. 2016-07-25. A general forcefield for accurate phonon properties of metal-organic frameworks. https://doi.org/10.1039/c6cp05106e

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