Ligand field photochemistry

Chromium, hexacyano-, 3, 703, 777 hexaamminecobaltate coordination isomerism, 1, 183 ligand field photochemistry, 1, 398 photochemistry excited states, 1, 398 production, 3, 704 Chromium, hexafluoro-, 3, 927 Chromium, hexabalo-, 3, 889 Chromium, hexaiodo-, 3, 766 Chromium, hexakis(dimethyl sulfoxide)-photoanation, 1, 399 Chromium, u-oxalatodi-reduction... 

Garcia CG, de Lima JF, Iha NYM. Energy conversion from the ligand field photochemistry to solar cells. Coord Chem Rev 2000 196 219-47. 

Until recently only scattered data were reported for the irradiation of Co (III) ammines in the wavelength region of the Li band 14, 15), With acidoammine complexes, the acido group may be reported to photo-aquate, but no ammonia aquation was looked for and the photochemistry appeared to be merely a catalysis of the thermal reaction. Reported quantum yields were low (except where CT character was present, in which case redox decomposition was also observed), and the ligand field photochemistry of this class of complexes seemed rather uninteresting. 

Chromium, hexaammine-hexacyanocobaltate coordination isomerism, 183 trioxalatoaluminum reactions, 27 Chromium, hexaaqua-electron transfer, 367 with hexaaquachromium, 370 with pentaamineisonicotinamidoruthenium, 367 with pentaaquahydroxychromium, 370 isomerism, 183 trichloride isomerism, 183 Chromium, hexacyano-hexamminecobaltate coordination isomerism, 183 ligand field photochemistry, 398 photochemistry excited states, 398... 

Chromium, tris(bipyridyl)-ligand field photochemistry, 398 photochemistry excited states, 398... 

Chromium, tris(hexafluoroacetylacetonato)-optical isomerism, 28 Chromium, tris(l,10-phenaiithroline)-ligand field photochemistry, 398 Chromium, tris(trifluoroacetylacetonato)-isomerism, 28 Chromium complexes geometric isomerism, 11 Chromium (0) complexes magnetic behavior, 273 Chromium(I) complexes magnetic behavior, 272 Chiomium(II) complexes magnetic behavior, 272 spectra, 252 thiocyanate... 

Plane34-38 and Schlafer37,39 have argued that the photochemistry initiated by irradiation of the ligand field absorption bands of chro-mium(III) complexes in aqueous solutions near room temperature can... 

CT excitation is more common in the photochemistry of coordination compounds. Besides the d — d transition (ligand field band), the CT band is often observed and the redox reaction between central metal ion and ligand is frequently induced by photoirradiation. This process has been used to initiate vinyl polymerization. 

Reviews have covered applications of ligand field theory to excited states and the photochemistry of complexes, especially those of Crin.130-133... 

Mixed-ligand Crm complexes have a particularly rich substitutional photochemistry in that two (or more) reaction modes are normally observed. Data for the well-studied class of acidoamine complexes are presented in Table 2. The dominant photochemical reaction for [CrX(NH3)5]2+ complexes in aqueous solution is NH3 aquation, with X- aquation occurring to a lesser extent (equation 31). In contrast, the latter pathway is the favored thermal reaction of these compounds. Such behavior again illustrates that the reactivity of ligand field excited states can differ sharply from that of the ground state. 

Ligand field transitions, and photochemistry, 1, 240 Ligand fragmentation, as metal vapor synthesis milestone,... 

The ligand field theory of transition metal photochemistry is based on the idea that the bonding changes in excited electronic states are correlated with ligand photolabilization (11-13). Populating the dz2 or dx2 y2 orbitals increases sigma antibonding in the z and xy directions respectively. 

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