CRYSTAL-STRUCTURE OF BA2LI2 3TI16 3O13

Single crystals of Ba2Li2/3Ti16/3O13 have been isolated and its crysta l structure solved from X-ray diffraction data. The structure is simil ar to that of Ba2Ti6O13 and Na2Ti6O13 [monoclinic, space group C2/m (n o.12), a= 15.171(13), b= 3.8992(18), c= 9.106(4) Angstrom, beta = 98.6 4(6)degrees, Z = 2], but one of the three independent octahedral sites contains partial substitution of Ti by Li, whereas the others are uni quely occupied by Ti. This phase contains only Ti4+,in contrast to Ba2 Ti6O13, which has a mixture of Ti3+ and Ti4+ The structure is describe d in terms of both an octahedral framework and a cubic close-packing m odel of [Ba-2 square O-13] layers (square:vacancy).