• Home
  • Search Results
  • Experimental and computational thermochemical study of barbituric acids: structure-energy relationship in 1,3-dimethylbarbituric acid.

Experimental and computational thermochemical study of barbituric acids: structure-energy relationship in 1,3-dimethylbarbituric acid.

The journal of physical chemistry. A (2011-03-25)
María Victoria Roux, Rafael Notario, Concepción Foces-Foces, Manuel Temprado, Francisco Ros, Vladimir N Emel'yanenko, Sergey P Verevkin
ABSTRACT

This paper reports an experimental and computational thermochemical study on 1,3-dimethylbarbituric acid. The value of the standard (p° = 0.1 MPa) molar enthalpy of formation in the gas phase at T = 298.15 K has been determined. The energy of combustion was measured by static bomb combustion calorimetry, and from the result obtained, the standard molar enthalpy of formation in the crystalline state at T = 298.15 K was calculated as -639.6 ± 1.9 kJ·mol(-1). The enthalpy of sublimation was determined using a transference (transpiration) method in a saturated N(2) stream and a value of the enthalpy of sublimation at T = 298.15 K was derived as 92.3 ± 0.6 kJ·mol(-1). From these results a value of -547.3 ± 2.0 kJ·mol(-1) for the gas-phase enthalpy of formation at T = 298.15 K was determined. Theoretical calculations at the G3 and G4 levels were performed, and a study on molecular and electronic structure of the compound has been carried out. Calculated enthalpies of formation are in very good agreement with the experimental value.

MATERIALS
Product Number
Brand
Product Description

Sigma-Aldrich
1,3-Dimethylbarbituric acid, ≥99.0% (T)

Social Media

LinkedIn icon
Twitter icon
Facebook Icon
Instagram Icon

MilliporeSigma

Research. Development. Production.

We are a leading supplier to the global Life Science industry with solutions and services for research, biotechnology development and production, and pharmaceutical drug therapy development and production.

© 2021 Merck KGaA, Darmstadt, Germany and/or its affiliates. All Rights Reserved.

Reproduction of any materials from the site is strictly forbidden without permission.