Sheet conductivity was detected in O-reduced samples. The sheets were aligned along the twin boundaries of the non-reduced starting material. The bulk transformed, during O loss, to give an O-deficient phase with a tetragonal crystal structure: P¯421m, a = 0.739, c = 0.388nm. The perovskite-like structure contained distorted octahedra with W-O distances ranging from 0.17 to 0.218nm.

A.Aird, M.C.Domeneghetti, F.Mazzi, V.Tazzoli, E.K.H.Salje: Journal of Physics - Condensed Matter, 1998, 10[33], L569-74