Calorimetric and computational studies for three nitroimidazole isomers

• Type: Article in International Scientific Journal
• Date: 2017

Authors

Carvalho, TMT (Author) Other; Amaral, LMPF (Author) FCUP; Morais, VMF (Author) Other; Maria D M C R Ribeiro da Silva (Author) FCUP

Journal

Title: Journal of Chemical Thermodynamics

Vol. 105

Pages: 267-275

ISSN: 0021-9614

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 8 Citations

Scopus - 8 Citations

Other information

Authenticus ID: P-00M-68Y

DOI: 10.1016/j.jct.2016.10.026

Abstract (EN): In the present work, a combined experimental and computational thermochemical study of nitroimidazole isomers was carried out. The standard (p = 0.1 MPa) molar enthalpy of combustion, in the crystalline phase, for 4-nitroimidazole was determined, at the temperature of 298.15 K, using a static bomb combustion calorimeter. Calvet microcalorimetry experiments were performed to measure its standard molar enthalpy of sublimation. The standard molar enthalpy of formation of 4-nitroimidazole, in the gaseous phase, at T = 298.15 K, (116.9 +/- 2.9) kJ.mol(-1), has been derived from the corresponding standard molar enthalpy of formation in the crystalline phase and the standard molar enthalpy of sublimation. Computational studies for 4-nitroimidazole were performed to complement the experimental work. These were also extended to the 2- and 5-nitroimidazole isomers. The gas-phase enthalpies of formation were estimated from high level ab initio molecular orbital calculations, at the G3 level. Also investigated were the tautomeric equilibrium of 4(5)-nitroimidazole in the gaseous phase and it was concluded that the two tautomers are equally stable. (C) 2016 Elsevier Ltd.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 9