6 Molecular Magnetism of Metal Complexes and Light-Induced …
279
Fig. 6.10 57 Fe Mössbauer spectra of (C 6 H 5 ) 4 P[Mn II Fe III (mto) 3 ] at 30, 22 and 10 K
6.3 Mixed-Valence System and Charger Transfer Phase
Transition
6.3.1 Classification of Mixed-Valence System
Mixed-valence compounds, defined as compounds containing an element with more
than one oxidation state, are classified into three groups according to the Robin–Day
classification [28],
Class I
Compounds whose valence states occupy different crystallographic
sites and are too distant from each other to allow the electronic
interaction between the mixed-valence states.
Class II
Compounds in which an electron exchange between the different
valence states takes place as a thermally activated process. The intervalence charge transfer (IVCT) between different valence states is
observable in optical absorption spectra.
279
Fig. 6.10 57 Fe Mössbauer spectra of (C 6 H 5 ) 4 P[Mn II Fe III (mto) 3 ] at 30, 22 and 10 K
6.3 Mixed-Valence System and Charger Transfer Phase
Transition
6.3.1 Classification of Mixed-Valence System
Mixed-valence compounds, defined as compounds containing an element with more
than one oxidation state, are classified into three groups according to the Robin–Day
classification [28],
Class I
Compounds whose valence states occupy different crystallographic
sites and are too distant from each other to allow the electronic
interaction between the mixed-valence states.
Class II
Compounds in which an electron exchange between the different
valence states takes place as a thermally activated process. The intervalence charge transfer (IVCT) between different valence states is
observable in optical absorption spectra.