Abstract
We succeeded in preparing several members of a new family of (Hg,Cr)Sr2Can-1CunOy superconductors under high-pressure at 6 GPa and 1000 degrees C. The phase formation was confirmed by X-ray and electron diffraction analyses as well as high-resolution electron microscopy. These compounds am tetragonal and analogs to HgBa2Can-1CunOy layerd cuprates with Ba completely substituted by Sr. The first important feature deals with the synthesis of 1212 phase, (Hg,Cr)Sr2CaCu2Oy, without additional elements like Y with T-c of 80 K. The second important point deals with the successful synthesis of higher members (n = 3-5) of this family fm the first time. The highest T-c of 98 K was observed fin (Hg,Cr)-1223 phase.