0.1 O 2.85 -The title phase is prepared by solid state reaction of a stoichiometric mixture of BaCO3, CeO2, In2O3, and Nd2O3 (800, 1100, 1400, and 800°C for 16, 10, 24, and 30 h, respectively). The product is phase-pure and crystallizes in the orthorhombic space group Pmcn as revealed by powder XRD. Its standard enthalpy of formation is determined by solution calorimetry. BaCe 0.7 Nd 0.2 In 0.1 O 2.85 is thermodynamically stable with respect to the binary oxides. -(MATSKEVICH*, N. I.; MATSKEVICH, M. Y.; WOLF, T.; BRYZGALOVA, A. N.; CHUPAKHINA, T. I.; ANYFRIEVA, O. I.; J. Alloys Compd. 577 (2013) 148-151, http://dx.