Preparation and Ligand Field Absorption Spectra of [CrF2(O–O)2]3− and [CrF2(O–O)(en)]− Type Complexes

Abstract

Abstract Two geometrical isomeric pairs of [CrF2(O–O)2]3− and either one of two possible geometrical isomers of [CrF2-(O–O)(en)]−, where O–O denotes oxalate and malonate anions, were newly prepared and characterized by means of the spectral and chromatographic elution behaviors. It was found that [CrF2(ox)(en)]− and [CrF2(mal)(en)]− obtained take cis and trans forms, respectively. The ligand field absorption spectra of the present complexes were compared with one another, and with those of the corresponding aqua complexes of the same type. On the basis of the analyses of the absorption spectra in terms of the angular overlap model, the AOM parameters (eσ and ex) for the ligands concerned were estimated, and their transferability assumption and the anisotropic π interactions of Cr–O bonding with respect to the chelate plane of the dicarboxylate ligands were discussed.