Single crystals of the Hg 1− x Pb x Ba 2 Ca n −1 Cu n O 2 n +2+ δ (x = 0 and 0.2) and infinite-layer CaCuO 2 compounds have been grown using a high gas pressure. The Hg 0.8 Pb 0.2 -1234 single crystals of a size up to 0.5×0.5×0.05 mm 3 have a T c onset of 129 K. Sing le crystals of the CaCuO 2 of a size up to 2×1×0.05 mm 3 have been obtained without stabilizing additives of Sr or Li. The T c onset varies between 70 and 100 K. X-ray structural refinements have been performed on the CaCuO 2 and Hg-1234 single crystals. HRTEM investigations proved a high quality of the crystal structure of the Hg-12 ( n -1) n crystals.
