HIGHER T-CS BY CHEMICAL SUBSTITUTIONS IN LAYERED CUPRATES CONTAINING HG IN THE RESERVOIR BLOCKS

In order to explain why Tc of all Hg-12(n-1)n compounds increases with pressure and decreases with chemical substitutions, the variation of the Hg-1223 structure as a function of external pressure is compared t o that induced in the same structure by total substitution of Ba with Sr and partial substitution of Hg with Re. The introduction of Sr in t he structure seems to induce all the structural changes needed to simu late the structure stable under pressure except the thickness of the s uperconducting blocks, which decreases with pressure and increases by Sr substitution. The Re substitution does not seem to play an importan t role except for the stability of the structure and seems to contribu te to produce overdoped samples.