Citation: Bordet, P; Chaillout, C; Capponi, J J; Chenavas, J; Marezio, M (1987). Crystal structure of Y~0.9~ Ba~2.1~ Cu~3~ O~6~, a compound related to the high-T~c~ superconductor Y Ba~2~ Cu~3~ O~7~.. Nature (London), 327, pp. 687-689.
Formula: Ba2.1 Cu3 O6 Y0.9
Chemical name:Yttrium barium copper oxide (.9/2.1/3/6) - prepared at T = 950 C