title: High pressure structural changes in aluminium triiodide: A first principles study.
abstract: First principles calculations identified a phase transition in aluminium triiodide (AlI3) and predicted its physical and spectroscopic properties under high pressure conditions. A high pressure monoclinic phase is predicted to exist above 1.3 GPa accompanied with a coordination change of aluminium resulting from a transformation from the ambient pressure 4-coordinated primitive monoclinic phase with space group P21/c to the monoclinic 6-coordinated structure with space group C2/m. Density functional phonon calculations predicted its dynamical and mechanical stability. Infrared effective charge intensities and Raman scattering tensors were obtained to characterize its spectroscopic properties. First-principles metadynamics simulations were employed to reconstruct this phase transition and provide the mechanism details for energetically favourable path from the ambient pressure P21/c structure to the predicted C2/m structure.
authors.affiliation: Department of Physics and Engineering Physics, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E2, Canada.
authors.forename: Arnab
authors.initials: A
authors.lastname: Majumdar
authors.affiliation: National Research Council of Canada, Ottawa, Ontario K1A 0R6, Canada.
authors.forename: Dennis D
authors.initials: DD
authors.lastname: Klug
authors.affiliation: Department of Physics and Engineering Physics, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E2, Canada.
authors.forename: Yansun
authors.initials: Y
authors.lastname: Yao