Decomplexation and complexation of alkali metal cations by a crown-ether-type podand in dichloromethane: a steered molecular dynamics study

• Tipo: Artigo em Revista Científica Internacional
• Data: 2012

Autores

Mario Valente (Autor) Outra; Sergio Filipe Sousa (Autor) FCUP; Magalhaes, AL (Autor) FCUP; Cristina Freire (Autor) FCUP

Revista

Título: Theoretical Chemistry Accounts

Vol. 131 Nº 3

Páginas: 1-7

ISSN: 1432-881X

Editora: Springer Nature

Indexação

ISI Web of Knowledge - 4 Citações

Scopus - 4 Citações

Classificação Científica

FOS: Ciências exactas e naturais > Química

Outras Informações

ID Authenticus: P-002-CDA

DOI: 10.1007/s00214-012-1171-5

Abstract (EN): The decomposition of three complexes involving the alkali metal cations Li+, Na+ and K+ and a potentially octadentate polyethylene-glycol-type podand(1,2-bis-{2-[2-(2-methoxy-ethoxy)-ethoxy]-ethoxy}-benzene, hereafter b33) in dichloromethane was studied by steered molecular dynamics (SMD). This technique proved applicable to the problem. Analysis of the resulting trajectories allowed phenomenological descriptions of the decomposition processes. Use of the Jarzynski identity allowed the estimation of the corresponding free energies, which in turn allowed the estimation of the complex formation free energies in dichloromethane. These are very similar to the experimental values determined by liquid-liquid extraction, as long as a strong reduction of the podand denticity is considered, possibly due to the presence of competing water molecules. To the best of our knowledge, the present study is the first to use SMD to address the problem of determination of the free energies involved in the complexation of alkali cations by an extraction agent (here a podand), in a bulk solvent (here dichloromethane).

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 7