Naturally occurring gem opals would seem to be the inspiration for the rece
nt explosion of work on three-dimensionally ordered macroporous, or "3DOM"
materials. Myriad techniques have been developed for the creation of 3DOM p
roducts. This work focuses on ordered metal oxides and the effects that the
chemistry behind precursors and template removal have on the phase and com
position of the end product. Structural features that affect the materials'
photonic, optical, catalytic, and magnetic properties are discussed.