Basic building units, self-assembly and crystallization in the formation of complex inorganic open architectures

Careful investigations of open-framework metal phosphates reveal that the f ormation of these complex architectures is likely to involve a process wher ein one-dimensional ladders or chains, and possibly zero-dimensional monome rs, transform to higher dimensional structures. The one-dimensional ladder appears to be the primary building unit of these structures. At one stage o f the building-up process, spontaneous self-assembly of a low-dimensional s tructure such as the ladder seems to occur, followed by crystallization of a two- or three-dimensional structure. Accordingly, many of the higher dime nsional structures retain the structural features of the 1D structure, indi cating the occurrence of self-assembly. These findings mark the beginnings of our understanding of complex supramolecular inorganic materials.