A new pentanuclear cyano-bridged complex [(Fe(II)(tetraazamacrocycle))3{mu-NC-FeIII(CN)5)2]: synthesis, spectroscopic and magnetic characterization.
Hexacyanoferrate(III) reacts with [FeII(meso)(CH3CN)2](ClO4)2.2CH3CN (meso=5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane) in acetonitrile/water mixture producing the title complex, where three [Fe(meso)]2+ units are connected by two [Fe(CN)6](3-) anions. Molecular modeling (MM+) shows a fairly linear molecule and Mössbauer data are consistent with two terminal pentacoordinated low spin iron(II)-meso units linked to one hexacoordinated low spin iron(II)-meso through two hexacoordinated low spin iron(III) units. Spectroscopic characterization showed a typical mixed-valence charge transfer band and the degree of electron coupling was calculated to be H(AB)=678 cm(-1). Magnetic properties exhibited an antiferromagnetic exchange interaction between the iron(III) ions with a coupling constant J= -44 cm(-1).
Ishiruji
Fabiana H O
FH
Departamento de Química, Universidade Federal do Paraná, Centro Politécnico, C.P. 19081, 81531-990, Curitiba, PR, Brazil.
Evans
David J
DJ
Benedito
Flávio L
FL
Nunes
Fábio S
FS
D003486:Cyanides / Q000737:chemistry*; D007501:Iron / Q000737:chemistry*; D008280:Magnetics; D008958:Models, Molecular; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000737:chemistry*; D013057:Spectrum Analysis; D013696:Temperature
D003486:Cyanides; D009942:Organometallic Compounds; D007501:Iron