The salts [Co(C5H5)2]+ wavelength absorptions at [Mn(CO)5]- and [Cr(C6H6)2]+ [Mn(CO)5]- show longwavelength absorptions at λmax 740 nm and 665 nm. These bands assigned to metal to metal charge transfer (MMCT) transitions from Mn-I to CoIII and CrI. Upon MMCT excitation the former ion pair is converted to Co(C5H5)2 and Mn 2(CO)10. The latter ion pair undergoes an analogous redox reaction as a thermal process. The thermal and the light-induced electron transfer are explained on the basis of the Hush model.