SYNTHESIS OF THE (GA, AL)SR2CAN-1CUNO2N-5) SYSTEMS AT AMBIENT-PRESSURE(3, (N=2)

Through an ambient pressure synthesis we have obtained a stable copper oxides for n > 3. Here we report a series of compounds given by (Ga, Al)Sr2Can-1CunO2n+3, (n = 2 - 5) prepared at ambient pressure. These c ompounds have a structural rearrangements which is different to those synthesized with high pressure [1-3], even though the thermodynamic ef fects at ambient conditions do not change regardless of structural cha nges. By X-ray diffraction we observe that the (Go, All-based compound s, which have a tetragonal cell, are isomorphous to the ones reported by Isobe ct al. [3] and Tl-based superconductor [4] respectively. For the Ga compounds the reaction temperature is 930 +/- 3 degrees C and f or the Al system is 970 +/- 3 degrees C.