Thermochemical and theoretical study of some methyldiazines

• Type: Article in International Scientific Journal
• Date: 1996

Authors

daSilva, MAVR (Author) FCUP; Morais, VMF (Author) ICBAS; Matos, MAR (Author) FCUP; Rio, CMA (Author) Other; Piedade, CMGS (Author) Other

Journal

Title: Structural Chemistry

Vol. 7

Pages: 329-336

ISSN: 1040-0400

Publisher: Springer Nature

Indexing

ISI Web of Knowledge - 31 Citations

Scopus - 30 Citations

Scientific classification

FOS: Natural sciences > Chemical sciences

Other information

Authenticus ID: P-001-DBR

Abstract (EN): The standard (p(0) = 0.1 MPa) molar enthalpies of formation for the liquid 2,3-dimethylpyrazine and trimethylpyrazine and the crystalline 2,3-dimethylquinoxaline and tetramethylpyrazine were derived from the standard molar enthalpies of combustion, in oxygen, at T = 298.15 K, measured by static-bomb combustion calorimetry. The standard molar enthalpies of vaporization or of sublimation for the same compounds were determined by Calvet microcalorimetry. Ab initio full geometry optimization at the 3-21G and 6-31G* levels were also performed for all the methylpyrazine isomers. MP2/RHF/3-21G//3-21G and DFT energies were also calculated for air the methylpyrazine isomers, thus allowing us to estimate their isodesmic resonance energies.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 8