ABSTRACT
The structural characteristics of solid oxides that influence their dissolution behavior include the crystal and molecular structure, the Madelung or cohesive energy of the crystal, the bond type, and the electronic structure. This chapter discusses the chemistry of metal oxides immersed in water. In the crystalline solid, individual electronic states may interact and form electronic bands. In purely ionic oxides, the covalent mixing of cation- and anion-centered levels is negligible, and only purely anionic and purely cationic bands need be considered. Crystal field theories are useful in describing the electronic structure of transition metal oxides in cases where the electronic interactions within a given atom or ion are much stronger than the interatomic interactions. Metal oxides constitute the basis of a large number of heterogeneous catalysts. Active catalysts interact rather strongly with gaseous molecules, and the bonds formed by surface atoms and adsorbates do not differ conceptually from those formed in bulk phases.
