NO Donor Schiff Base Research Articles

Magnetic and spectral properties of oxovanadium(IV) complexes of schiff bases derived from halo-substituted salicylaldehyde and aniline

The magnetic and spectral properties of oxovanadium(IV) complexes of bidentate monobasic NO donor Schiff bases derived from 5-chlorosalicylaldehyde, 5-bromosalicyl-aldehyde and aniline are reported. In contrast to an earlier report that the complexes are involved in antiferromagnetic exchange, magnetic, ESR and molecular weight data indicate that the complexes are magnetically dilute. The complexes are monomers. The ESR spectra of the complexes in chloroform solutions show 8-line spectra characteristic of oxovanadium(IV) complexes which are not involved in magnetic exchange. The complexes exhibit magnetic moments in the range 1.73–1.75 B.M. at ~ 295 K and obey the Curie-Weiss law with θ = 0 to + 2 K indicating the absence of magnetic ordering in the temperature range 83–296 K.The electronic and infrared spectral data of the complexes are also reported. In contrast to an earlier suggestion of dimeric structure, a monomeric structure with square-pyramidal geometry is suggested for the complexes.