Inorganic Chemistry, Vol.37, No.20, 5227-5232, 1998
Ab initio calculations of the trigonal and zero-field splittings in trischelated diketonato complexes of trivalent chromium
The ground and excited states of the neutral tris(1,3-propacedionato)chromium(III) d(3) complex an investigated with quantum chemical methods. Trigonal splittings are calculated and compared with experiment for the first two excited quartet states T-4(2g) and T-4(1g). The effect of spin-orbit coupling is also introduced, and a reassignment is proposed for three absorption bands in the doublet region. Trigonal symmetry-induced mixing between the e(g) and t(2g) shells is found to be responsible for the unusually large zero-field splitting of the T-4(2g) ground state. Orbitals pictures are presented which illustrate the role of the phase-coupling effect from the unsaturated ligands.
Keywords:CONJUGATED BIDENTATE LIGANDS;TRANSITION-METAL COMPLEXES;ANGULAR OVERLAP MODEL;LEVEL SPLITTINGS;DOUBLET STATES;EXCITED-STATES;TRIS(ACETYLACETONATO)CHROMIUM(III);CR(ACAC)3;ABINITIO;SPECTRA