No abstract

No abstract

No abstract

No abstract

No abstract

No abstract

No abstract

The consmction of accurate pseudopotentials with good convergence propexties for the first-row and vansition elements is discussed. We show that by combining an improved description of the pseudowavefunction inside the cut-off radius with the concept of ultrasoft pseudopotentials introduced by Vanderbill optimal compromise between hansferability and plane-wave convergence can be achieved. W i t h the new pseudopotentials, basis sets with no more than 75-100 plane waves per atom m sufficient to reproduce the results obtained with the most accurate nom-canserving pseudopotentials.