THE ELIMINATION OF LANCZOS GHOSTING EFFECTS BY MINRES FILTER DIAGONALIZATION

A recently developed filter diagonalization technique (Ber. Bunsenges. Phys. Chem. 101, 400, 1997), based on the optimal approximation of th e Green operator in a finite Lanczos subspace, is investigated in rela tion to its ability to avoid the phenomenom of ghosting which complica tes the interpretation of the regular Lanczos spectrum as the order of the subspace is increased. The origin of this potentially useful prop erty of the algorithm is explained with reference to one- and two-dime nsional applications. (C) 1998 Academic Press.