Thermochemical and theoretical study of some methyldiazines

• Tipo: Artigo em Revista Científica Internacional
• Data: 1996

Autores

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

Revista

Título: Structural Chemistry

Vol. 7

Páginas: 329-336

ISSN: 1040-0400

Editora: Springer Nature

Indexação

ISI Web of Knowledge - 31 Citações

Scopus - 30 Citações

Classificação Científica

FOS: Ciências exactas e naturais > Química

Outras Informações

ID Authenticus: 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.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 8