@Article{InorgChem_35_2077,
author = {T. Sch{\"o}nherr and M. Atanasov and A. Hauser},
title = {{Role of $\pi$-Bonding for Trigonal Level Splittings in Chromium(III) Complexes. 4. Doublet States and Zeeman Level Splittings in [Cr(bpy)$_3$]$^{3+}$}},
journal= {Inorg. Chem.},
ISSN = {0020-1669},
volume= {35},
number= {7},
pages = {2077-2084},
url = {http://pubs.acs.org/doi/abs/10.1021/ic950150o},
doi= {10.1021/ic950150o},
abstract = {{A detailed analysis of Zeeman splittings of highly resolved spin-forbidden transitions in [Cr(bpy)$_3$](PF$_6$)$_3$ is presented. Assignments of vibronic bands are made based on low-temperature absorption, emission, and infrared spectra. The pattern of doublet states, obtained for H = 0 and H = 5 T, is consistent with angular overlap model (AOM) calculations, which allow one to consider $\sigma$- and $\pi$-interactions between the metal-d and relevant ligand orbitals and the particular angular geometry of the chromophore simultaneously. The observed level splittings are found to result from the combined effect of trigonal distortion and contributions of the symmetry adapted d$_{\pi}$-orbitals involved due to coupling with corresponding counterparts from the bidentate ligand ({\em phase coupling}). The larger splitting of the lowest excited state $^2$E$_{g}$({\em O}{\em $_{h}$}) in the analogous ClO$_{4}^-$ salt is due to the more distorted geometry of the [CrN$_{6}$] moiety. Related properties of the bipyridine ligand, which turn out to show donor behavior in the present compounds, and the acetylacetonate ligand are discussed, and AOM parameters for the metal-ligand $\pi$-interaction are correlated with results of MO calculations.}},
year = {1996}
}