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Updated: Aug 11, 2026

Spatial Separation of Molecular Conformers and Clusters
Published on: January 9, 2014
Internal rotation in 1,2-di-(p-XC6H4)ethanes (X=H, Br, NO2): infrared spectra and compensation effect
D I Kamalova1, S A Petrova, A B Remizov
1Kazan State University, Kremlevskaya St. 18, Kazan 420008, Russia. dina.kamalova@ksu.ru
Abstract:
Infrared absorption spectra and internal rotation of 1,2-di-(p-XC(6)H(4))ethanes (X=H, Br, NO(2)) in crystalline phase, liquid and solutions at various temperatures have been investigated. Band fitting was applied to conformationally sensitive regions of the spectra, and assignment of the peaks to trans and gauche conformations was performed. Enthalpy and entropy differences of the conformers (deltaH(0) and deltaS(0)) were found to be solvent-dependent, and it is interpreted in terms of previously discovered compensation effect. The values deltaH(0) and deltaS(0) for 1,2-di-(p-NO(2)C(6)H(4))ethane obtained are unusually large.
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