Microstructural Characterization of the LaNiO3-y System

M.J. SAYAGUEZ; A. CANEIRO; J.M. GONZALEZ CALBET; M. VALLET-REGI

JOURNAL OF SOLID STATE CHEMISTRY

ACADEMIC PRESS INC ELSEVIER SCIENCE

Lugar: Amsterdam; Año: 1994 vol. 110 p. 295 - 304

0022-4596

An electron diffraction and high-resolution electron microscopy study of the LaNiO3-y perovskite-related system shows that compositional variations lead to the formation of new superstructures corresponding to a homologous series of the general formula LanNinO3n-1 when y = 0.5 and 0.25, i.e., for n = 2 and 4, respectively. These members can be described as being formed by ordered intergrowths of (n - 1) octahedral layers alternating with one layer in which Ni2+ adopts square planar coordination. For different y values, the nonstoichiometry is accommodated by means of disordered intergrowths of octahedral and square-planar layers.