HOLES IN DIAMOND OR CARBON NITRIDE LATTICES

A discussion is presented for possible diamond-lattice-based structure s containing holes that can be filled with metal atoms or ions. To all ow the formation of coordinative bonds to the metal, some carbon atoms should be replaced by heteroatoms (with nitrogen preferred, but in so me cases oxygen or other heteroatoms may be considered). Two types of holes that may lead to the formation of coordinative bonds are discuss ed in detail: tetrahedral holes for four such bonds and quasi-octahedr al holes for six such bonds. In turn, when suitably arranged in a tran slationally symmetric manner, these holes may resemble open or closed pores in foams; when they are open, the ''channels'' may lead to inter esting properties with regard to metallic conductivity or superconduct ivity. (C) 1996 John Wiley & Sons, Inc.