ELECTRONIC-STRUCTURE, NESTING FEATURES AND VANHOVE SINGULARITIES IN THE MERCURY-BASED HIGH T-C COMPOUNDS CONTAINING 1 TO 5 CUO2 LAYERS

A systematic study of the band structure, Fermi surface, density of st ates and the (q) over right arrow dependence of the electronic suscept ibility has been performed from first principles within the local dens ity approximation using the Full Potential Linear Muffin Tin Orbital M ethod (LMTO) for Hgba(2)Ca(n-1)Cu(n)O(2n+2)(n = 1 - 5). A comparisson for the whole series is presented. Hole doping by addition of 0 in the 0(4) site in the Hg plane or the effect of pressure can be modeled by moving EF close to the van Hove singularities. Changes of the nesting features with this modeled hole doping or pressure are discussed.