Temperature Evolution of Methylammonium Trihalide Vibrations at the Atomic Scale A. Mattoni, * A. Filippetti, M.I. Saba, C. Caddeo, and P. Delugas Istituto Ocina dei Materiali, CNR-IOM SLACS Cagliari, 09042 Monserrato (CA) E-mail: mattoni@iom.cnr.it 1 This document is the Accepted Manuscript version of a Published Work that appeared in final form in THE JOURNAL OF PHYSICAL CHEMISTRY LETTERS, J. Phys. Chem. Lett. 2016, 7, 3, 529–535 Copyright © 2016 American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://doi.org/10.1021/acs.jpclett.5b02546