Neutron Diffraction Study of the Crystal Structure of BaMoO4: a Suitable Precursor for Metallic BaMoO3 Perovskite

VIVIAN NASSIF; RAÚL E. CARBONIO; JOSÉ A. ALONSO

Elsevier

Año: 1999 vol. 146 p. 266 - 266

font size="1" face="MathPackThree"> BaMoO3, metallic and Pauli paramagnetic, has been prepared by controlled reduction of BaMoO4. This precursor, containing Mo(VI), is unusually stable against reduction, due to structural factors. The crystal structure of BaMoO4 has been refined from neutron powder diffraction data: space group I41/a (no. 88), Z=4, a=5.5479(9), and c=12.743(2) Å . A bond valence study allowed us to detect the presence of slight tensile and compressive stresses in the crystal structure of BaMoO4, in which Ba is overbonded and Mo is underbonded. However, this effect is less pronounced than in other AMO4 oxides with a scheelite structure (A=Ca,