Patent ID: 7554029

Claim:
A complex oxide comprising: a layer-structured oxide represented by the formula Bi a Pb b M 1 c Co d M 2 e O f wherein M 1 is one or more elements selected from the group consisting of Na, K, Li, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Pb, Ca, Ba, Al, Y, and lanthanoids; M 2 is one or more elements selected from the group consisting of Ti, V, Cr, Mn, Fe, Ni, Cu, Mo, W, Nb, Ta, and Ag; 1.8≦a≦2.5; 0≦b≦0.5; 1.8≦c≦2.5; 1.6≦d≦2.5; 0≦e≦0.5; and 8≦f≦10; and at least one interlayer component selected from the group consisting of F, Cl, Br, I, HgF 2 , HgCl 2 , HgBr 2 , HgI 2 , TlF 3 , TlCl 3 , TlBr 3 , TlI 3 , BiF 3 , BiCl 3 , BiBr 3 , BiI 3 , PbF 2 , PbCl 2 , PbBr 2 , and PbI 2 ; the interlayer component being present between layers of the layer-structured oxide.