Synthesis and density functional calculations of the new molecule-based magnet precursor [Fe(H2opba-i)(dmso)2]Cl

• Autor(a) principal: Souza,Gilmar P.
• Data de Publicação: 2006
• Outros Autores: Konzen,Cibele, Ardisson,José D., De Abreu,Heitor A., Duarte,Hélio A., Alcântara,Antônio F. C., Nunes,Wallace C., Macedo,Waldemar A. A., Knobel,Marcelo, Stumpf,Humberto O.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Journal of the Brazilian Chemical Society (Online)
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532006000800008
• topic: molecule-based magnet; oxamate; iron(III); PBE/DZVP theoretical calculations; cis/trans isomerism

A new precursor of molecule-based magnetic systems, [Fe(H2opba-i)(dmso)2]Cl (1), with opba = ortho-phenylenebis(oxamato) in an iminoalcohol tautomeric form, was obtained as a product from the reaction between H4opba and FeCl3. Data from elemental analysis, IR and Mössbauer spectroscopies and magnetic measurements indicate that this precursor is composed of a mixture of trans (83%) and cis (17%) isomers. The chiMT value at 298K (2.1 emu K mol-1) corresponds to FeIII with spin state (S) between 3/2 and 5/2. Theoretical calculations (PBE/DZVP2) of trans- and cis-[Fe(H2opba-i)(dmso)2 ]+ show that both isomers have spin S = 1/2 in the ground state and S = 3/2 for the trans and S = 5/2 for the cis in the first excited state. The combination of these results leads to chiMT values of 0.375 and 2.3 emu K mol-1, at low and high temperature respectively, which are in accordance with the experimental data for 1.