SPECTROCHEMICAL PROPERTIES OF NONCUBIC TRANSITION-METAL COMPLEXES IN SOLUTIONS .6. ANGULAR OVERLAP TREATMENT OF TRANS-[CRFX(EN)2]+ (X=CL-, BR- AND NCS-) COMPLEXES IN AQUEOUS-SOLUTION

A series of trans-[CrFX(en)2]+ complexes (en = ethylenediamine, X = Cl-, Br- and NCS-) has been prepared. Electronic spectra of aqueous solution of these complexes have been measured and interpreted using the angular overlap model (AOM) assuming C2v as the effective symmetry. All d-d transitions, which are required in the ligand field (LF) theory (except those energetically higher than the range of the measured spectrum) taken from the Gaussian analysis of the spectrum, have been used to calculate of AOM parameters. The values of the obtained parameters have been discussed in terms of the chemical utility and their relation to ligand-field strength. The comparison of described bonding properties of these mixed axial ligand complexes with parent trans-[CrF2(en)2]+ has been discussed. The influence of the axial ligand into the sigma- and pi-bonding properties of the other has been discussed.