Metal charge transfer

Mn(acac)3 in the above mechanism undergoes an intramolecular photooxidation-reduction reaction arising from the ligand to metal charge transfer process (LMCT). 

These iridium(IV) complexes have UV-visible spectra dominated by intense absorptions around 500 nm (X = Cl) and 700 nm (X = Br) assignable to 7tx —> Ir(t2g) ligand-to-metal charge-transfer bonds. 

FIGURE 16.33 In a ligand-to-metal charge-transfer transition, an energetically excited electron migrates from a ligand to the central metal ion. This type of transition is responsible for the intense purple of the permanganate ion, MnCF,. ... 

This paper surveys several aspects of metal-to-metal charge-transfer transitions. Species of interest originate from non-molecular and molecular solids and from solutions. The parallel in the different approaches is stressed. In addition to the spectroscopy of these transitions, their influence or role in other phenomena is also discussed. 

Metal-to-Metal Charge Transfer (MMCT) Involving One Closed-Shell... 

In this paper we will describe and discuss the metal-to-metal charge-transfer transitions as observed in optical spectroscopy. Their spectroscopic properties are of large importance with regard to photoredox processes [1-4], However, these transitions are also responsible for the color of many inorganic compounds and minerals [5, 6], for different types of processes in semiconductors [7], and for the presence or absence of certain luminescence processes [8]. 

In this chapter we have shown that optical metal-to-metal charge-transfer transitions are of large importance in many fields and that they occur very generally. Not only their direct, but also their indirect influence is of great importance. A more unified approach in the different areas of research, and a stronger interaction between the different approaches is desirable. 

Lin, W. and Frei, H. (2005) Photochemical C02 splitting by metal-to-metal charge-transfer excitation in mesoporous ZrCu (I)-MCM-41 silicate sieve. Journal of the American Chemical Society, 127 (6), 1610-1611. 

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