The crystal structures of Ta22W4067 [Mr --5788.19, a = 6.1485 (5), b = 47.6205 (12), c = 3.8559 (3)A, y = 90.04(1) °, space group = Cll2/m (non-standard setting), Z = 1, Dx = 8.513 gcm -3, F(000) = 2438] and Ta74W60203[Mr = 17741.06,a = 6.1664 (5), b ...