Interplay of Intra- and Intermolecular Interactions in Solid Iodine at Low Temperatures: Experimental and Theoretic Spectroscopy Study

I D Yushina; B A Kolesov

doi:10.1021/acs.jpca.9b01167

Interplay of Intra- and Intermolecular Interactions in Solid Iodine at Low Temperatures: Experimental and Theoretic Spectroscopy Study

J Phys Chem A. 2019 May 30;123(21):4575-4580. doi: 10.1021/acs.jpca.9b01167. Epub 2019 May 17.

Authors

I D Yushina¹, B A Kolesov^{2

3}

Affiliations

¹ South Ural State University , Chelyabinsk 454080 , Russia.
² A.V. Nikolaev Institute of Inorganic Chemistry, Siberian Branch , Russian Academy of Sciences , Novosibirsk 630090 , Russia.
³ Faculty of Physics , Novosibirsk National State Research University , Novosibirsk 630090 , Russia.

PMID: 31063373
DOI: 10.1021/acs.jpca.9b01167

Abstract

This work is devoted to the discussion of structural changes in crystalline iodine under low temperature studied from experimental and theoretic points of view. Experimental Raman spectra in the temperature range 5-300 K demonstrated unusual behavior of stretching vibration at ∼180 cm^-1 with temperature. The data allowed obtaining of ω( T) functions for both external translational and internal stretching modes of I₂. It was found that ω( T) trends significantly differ in comparison to typical van der Waals crystal α-S₈. The observed anomalies are explained from a theoretic point of view because of the strengthening of intralayer halogen bonding between I₂ molecules.