Chromium complexes charge-transfer transitions

Robert Plane I would like to comment on the photochemistry of these complexes, particularly the chromium which I think are well chosen for at least two of Dr. Gray s reasons. First, in the case of chromium, unlike cobalt, the charge transfer band is well separated, so that one can study the d-d transitions, at least in certain systems where one has six ligands all alike, and there is no Jahn-Teller splitting, and one has a fairly good idea as to the assignment of bands. 

Subsequently, similar calculations have been made on both ferrocene and dibenzene chromium by Shustorovich and Dyatkina (65), on the ring-metal bonding in the tricarbonylarene chromiums (63), and on ring-metal bonding in the general sandwich molecule (CWHW)2M, with n = 4,..., 8 and M a transition metal (66). The same author has also discussed charge-transfer effects in complexes of the type [CwH M(CO)3] and concludes that maximum transfer occurs for n = 6 (67). The general results of these theories are reasonable but detailed comment is reserved for Sec. III. 

The charge transfer absorption band of the chromium to benzene ring transition in 28 and its derivatives is found at considerably longer wavelengths than in the reference complex 158a (Fig. 38) [29, 40, 123]. The corresponding bis(tricarbonylchromium) complexes show a further bathochromic shift [29,40,... 

Chromium, Molybdenum, and Tui isten.—A review of substituent effects in organo-transition-metal complexes includes discussion of the properties of benchrotrene derivatives. There have been studies of charge-transfer complexation of [( -arene)M(CO)3] (M=Cr, Mo, and W) with -acceptor molecules, ... 

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