A new ( Hg , V )-based 1212-type cuprate ( Hg , V ) Sr 2 ( Y , Ca ) Cu 20 z with Tc ( on . set ) UP to 110 K 0

We have successfully synthesized a new (Hg,V)based 1212-type cuprate (Hg, -,VJ Srz(Y1 -,Cay) Cu,O,. The electrical resistance measurements showed that some of the as-synthesized materials with proper Hg/V and Y/Ca ratios exhibit weak superconductivity. Oxygen-annealing significantly improved their superconducting behavior, and T,( ,. up to 110 K was observed. The lattice parameters of (H V)-1212 were found to be in the f order of a = 3.8415(1) and c = 11.8514(6) A. Substitu ting mercury atoms by vanadium ones results in an important increase of the a parameter and an important decrease of the c parameter compared to the known Hgbased Sr-bearing compounds. The crystal structure of (Hg, V). 121 2 was refined by Rietveld refinement against X-ray powder data using the tetragonal symmetry of space group #'4/mmm. The V and Cu valence states and uctivity in this new (Hg, V)-1212 cuprate are PACS: 74.704; 74,70.Vy; 74.60.Mj