TOPOLOGICAL ANALYSIS OF THE CHARGE-DENSITY OF SOLIDS - BCC SODIUM AND LITHIUM

Studies of electronic structure of solids have concentrated mainly on Hilbert space properties such as energy-band structures and density of states, as well as some properties that can be reduced from them. Here, we report application of the topological charge density analysis to crystals. It is found that the pseudoatoms (or nonnuclear attractors, which are charge accumulations in nonnuclear regions), first found in Li-2, exist in solid lithium and sodium as well. In the former, the pseudoatoms form a connected network; in the latter, they are separated from one another. Although such networks obey the space group symmetry of the corresponding crystal, their existence is an intrinsic property of a specific crystal. (C) 1993 John Wiley & Sons, Inc.