STRUCTURALLY CONFINED TRANSITION-METAL OXIDE LAYERS, CHAINS AND OLIGOMERS IN MOLECULAR AND EXTENDED MAGNETIC SOLIDS

In an attempt to abstract the structural units of widely known silicat e, phosphate, and arsenate compounds based on a transition-metal oxide (TM oxide) framework, we have gained some new insight into the study of ''nanostructured'' materials and their corresponding electronic and magnetic properties. In this review, we highlight some of the feature s associated with the nanosized TM oxide frameworks observed in this s pecial class of oxides. Structurally, these oxides adopt a mixed frame work that is composed of interlinked MO6 (M = transition-metal cation) octahedra and XO4 (X = Si4+, P5+, As5+) tetrahedra. TM oxide octahedr a may share vertexes, edges, and faces to form nanoscale layers, chain s, and oligomers. These structurally well-defined low-dimensional latt ices are of experimental and theoretical importance in the sense that electron interaction can be studied in a confined space. In this revie w, we will illustrate these structurally confined TM oxide frameworks, including those observed in molecular complexes.