Order-disorder of oxygen anions and vacancies in solid solutions of La2TiO5 and La4Ga2O9.
Successful Rietveld refinements of seven compounds with the formulae La2Ti((1-x))Ga(x)O((5-x/2)), where x = 0.00, 0.20, 0.50, 0.70, 0.90, 0.95 and 1.00, were performed in order to describe the solid solubility between orthorhombic (Pnam) La2TiO5 and monoclinic (P2(1)/c) La4Ga2O9. The relationship between the end-member structures, which are already known, is discussed; the space-group change is a consequence of ordering the oxygen vacancies that become more numerous as Ga is substituted for Ti. The structures of the solid solutions are also described. The lengths of cell edges obey Vegard's rule.
Kasunic
Marta
M
Faculty of Chemistry and Chemical Technology, University of Ljubljana, Askerceva 5, 1000 Ljubljana, Slovenia.
Meden
Anton
A
Skapin
Sreco D
SD
Suvorov
Danilo
D
Golobic
Amalija
A