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

Journal of the Brazilian Chemical Society

Nunes, Wallace C.¹  Ardisson, José D.¹  Centro de Desenvolvimento da Tecnologia Nuclear, Belo Horizonte, Brazil¹  Stumpf, Humberto O.¹  Knobel, Marcelo¹  Konzen, Cibele¹  De Abreu, Heitor A.¹  Universidade Estadual de Campinas, Campinas, Brazil¹  Universidade Federal de Minas Gerais, Belo Horizonte, Brazil¹  Duarte, Hélio A.¹  Macedo, Waldemar A. A.¹  Alcântara, Antônio F. C.¹  Souza, Gilmar P.¹ 

关键词: molecule-based magnet;    oxamate;    iron(III);    PBE/DZVP theoretical calculations;    cis/trans isomerism;   

DOI  :  10.1590/S0103-50532006000800008

学科分类：化学（综合）

来源: SciELO

【 摘 要 】

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 cMT 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 cMT 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.

【 授权许可】

Unknown