title: PDielec: The calculation of infrared and terahertz absorption for powdered crystals.
abstract: The Python package PDielec is described, which calculates the infrared absorption characteristics of a crystalline material supported in a non-absorbing medium. PDielec post processes solid-state quantum mechanical and molecular mechanical calculations of the phonons and dielectric response of the crystalline material. Using an effective medium method, the package calculates the internal electric field arising from different particle morphologies and calculates the resulting shift in absorption frequency and intensity arising from the coupling between a phonon and the internal field. The theory of the approach is described, followed by a description of the implementation within PDielec. Finally, a section providing several examples of its application is given. © 2016 The Authors. Journal of Computational Chemistry Published by Wiley Periodicals, Inc.
authors.affiliation: School of Life Sciences, University of Bradford, Bradford, BD7 1DP, United Kingdom.
authors.forename: John
authors.initials: J
authors.lastname: Kendrick
authors.affiliation: School of Chemistry, University of Leeds, Leeds, LS2 9JT, United Kingdom.|School of Electronic and Electrical Engineering, University of Leeds, Leeds, LS2 9JT, United Kingdom.
authors.forename: Andrew D
authors.initials: AD
authors.lastname: Burnett
keywords: effective medium theory; infrared spectroscopy; permittivity; phonon; solid state DFT; terahertz spectroscopy