Cardiff University | Prifysgol Caerdydd ORCA
Online Research @ Cardiff 
WelshClear Cookie - decide language by browser settings

Temperature-dependent structural properties, phase transition behavior, and dynamic properties of a benzene derivative in the solid state

Zhou, Yating, Patterson, Rhian, Williams, P. Andrew, Kariuki, Benson M., Hughes, Colan E., Samanta, Ranita, Devarapalli, Ramesh, Reddy, C. Malla, Apperley, David C. and Harris, Kenneth D. M. 2019. Temperature-dependent structural properties, phase transition behavior, and dynamic properties of a benzene derivative in the solid state. Crystal Growth and Design 19 (4) , pp. 2155-2162. 10.1021/acs.cgd.8b01775
Item availability restricted.

[img] PDF - Accepted Post-Print Version
Restricted to Repository staff only until 7 March 2020 due to copyright restrictions.

Download (788kB)

Abstract

We report the solid-state structural properties and phase transition behavior of 1,4-dibromo-2,3,5,6-tetramethylbenzene, demonstrating that this material undergoes an order–disorder phase transition below ambient temperature (at ca. 154 K on cooling and ca. 160 K on heating). In both the high-temperature and low-temperature phases, the crystal structure is based on π-stacking of the molecules. In the crystal structure of the high-temperature phase, the bromine occupancy in each substituent site is ca. 1/3 and the methyl group occupancy in each substituent site is ca. 2/3, consistent with statistical orientational disorder of the molecule between six distinct orientations. Natural-abundance solid-state 2H NMR spectroscopy confirms that, at ambient temperature, this disorder is dynamic via rapid molecular reorientation about an axis perpendicular to the aromatic ring. In the low-temperature phase, the bromine and methyl substituents occupy preferred sites within the crystal structure, with the distribution of site occupancies becoming progressively more ordered on decreasing temperature.

Item Type: Article
Date Type: Publication
Status: Published
Schools: Chemistry
Advanced Research Computing @ Cardiff (ARCCA)
Publisher: American Chemical Society
ISSN: 1528-7483
Date of First Compliant Deposit: 8 April 2019
Date of Acceptance: 7 March 2019
Last Modified: 15 Aug 2019 14:31
URI: http://orca.cf.ac.uk/id/eprint/121602

Actions (repository staff only)

Edit Item Edit Item

Downloads

Downloads per month over past year

View more statistics