METAL COMPLEX OXIDE HAVING NEW CRYSTAL STRUCTURE AND USE THEREOF FOR IONIC CONDUCTOR

摘要

PROBLEM TO BE SOLVED: To provide an ionic-conductive substance having a new crystal structure.SOLUTION: The substance is a metal complex oxide having a new crystal structure satisfying conditions (a) to (c): (a) belonging to a space group of Fd-3m; (b) having a lattice constant within a range of 17.0±1.0 Å; and (c) having crystalline arrangement in a unit lattice where cations occupy at respective site occupancies shown in Table 1. Preferably, it is a barium-tungsten complex oxide and/or a derivative thereof.