SYNTHESIS AND CRYSTAL-STRUCTURE OF LIXTI3O6 (X=0.74) - AN INTERGROWTHPHASE OF RUTILE AND RAMSDELLITE STRUCTURE

A new lithium titanate bronze, LixTi3O6 (x = 0.74), is black in color and crystallizes in monoclinic symmetry, space group C2/m with a = 14. 1198(11) Angstrom, b = 2.9486(11) Angstrom, c = 4.9373(13) Angstrom, b eta=92.693(14)degrees, and Z=2. The structure was determined from a si ngle-crystal X-ray study and refined to the conventional values R = 0. 043 and wR = 0.036 for 1022 observed reflections, The basic units of t he structure are built up from rutile-type and double-rutile-type edge -shared TiO6 chains along the b axis, Lithium atoms are located in the ramsdellite-type tunnel sites with an occupancy factor of 0.37(2), Th is compound can be described as an intergrowth phase between ramsdelli te-type Li0.5TiO2 and rutile-type TiO2. (C) 1997 Academic Press.