Bonding energetics in alkaline metal alkoxides and phenoxides

• Autor(a) principal: Nunes, Paulo
• Data de Publicação: 2003
• Outros Autores: Leal, J.P., Cachata, V., Raminhos, H., Piedade, M.E.M.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10400.15/4531
• topic: alkaline metals; enthalpy of formation; lattice energy; thermochemical radii; thermochemistry

The bonding energetics in a variety of alkaline metal, alkoxides and phenoxides, MOR, was investigated based on the corresponding enthalpies of formation in the crystalline state determined by reaction-solution calorimetry. The results obtained at 298.15 K were as follows: fHom (MOR, cr)/kJmol-1 = 382.7 ± 1.4 (LiOC6H5), 513.6 ± 2.5 (NaO-nC6H13), 326.4 ± 1.4 (NaOC6H5), 375.2 ± 3.4 (KOCH3), 434.5 ± 2.7 (KOC2H5), 467.1 ± 5.2 (KOnC3H7), 459.3 ± 2.1 (KO-nC4H9), 464.6 ± 5.7 (KO-tC4H9), 464.3 ± 2.5 (KO-nC6H13), 333.3 ± 3.1 (KOC6H5), 380.6 ± 2.9(RbOCH3), 434.1 ± 2.9 (RbOC2H5), 345.3 ± 2.9 (LiOC6H5), 379.1 ± 3.0 (CsOCH3), 432.3 ± 3.1 (CsOC2H5), 466.9 ± 5.0 (CsO-nC3H7), 461.3 ± 3.5 (CsO-nC4H9), 461.9 ± 2.5 (CsO-tC4H9), 349.2 ± 1.4 (CsOC6H5). These results together with revised fH om (MOR, cr) values from the literature, were used to derive a consistent set of lattice energies for the MOR compounds and discuss general trends in the structure-energetics relationship based on the Kapustinskii equation.