𝔖 Bobbio Scriptorium
✦   LIBER   ✦

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

✍ Scribed by Vivian Nassif; Raúl E. Carbonio; José A. Alonso

Publisher
Elsevier Science
Year
1999
Tongue
English
Weight
176 KB
Volume
146
Category
Article
ISSN
0022-4596

No coin nor oath required. For personal study only.

✦ Synopsis

BaMoO 3 , metallic and Pauli paramagnetic, has been prepared by controlled reduction of BaMoO 4 . This precursor, containing Mo(VI), is unusually stable against reduction, due to structural factors. The crystal structure of BaMoO 4 has been re5ned from neutron powder di4raction data: space group I4 1 /a (no. 88), Z ‫؍‬ 4, a ‫؍‬ 5.5479(9), and c ‫؍‬ 12.743(2) A s . A bondvalence study allowed us to detect the presence of slight tensile and compressive stresses in the crystal structure of BaMoO 4 , in which Ba is overbonded and Mo is underbonded. However, this e4ect is less pronounced than in other AMO 4 oxides with a scheelite structure (A ‫؍‬ Ca, Sr, Ba; M ‫؍‬ Mo, W): BaMoO 4 contains the M cation exhibiting the closest valence to the nominal value of 6؉, suggesting a large covalent contribution to the Mo+O bonds. This observation is coherent with the large thermal stability of this compound against reduction, taking place at temperatures above 9203C in H 2 6ow.

📜 SIMILAR VOLUMES

Neutron Powder Diffraction Study of the
Neutron Powder Diffraction Study of the Crystal Structure of YSr2AlCu2O7
✍ Q. Huang; S.A. Sunshine; R.J. Cava; A. Santoro 📂 Article 📅 1993 🏛 Elsevier Science 🌐 English ⚖ 244 KB

The structure of \(\mathrm{YSr}_{2} \mathrm{AlCu}_{2} \mathrm{O}_{7}\) has been analyzed by neutron powder diffraction techniques. This compound crystallizes with space group \(P 4 / \mathrm{mm} m\) symmetry and with lattice parameters \(a=3.8646(1)\), \(c=11.1139(3) \AA\). The general structural fe

Neutron and X-Ray Diffraction Study of t
Neutron and X-Ray Diffraction Study of the Crystal Structure of CsTiSi2O6.5
✍ M.L. Balmer; Q. Huang; W. Wong-Ng; R.S. Roth; A. Santoro 📂 Article 📅 1997 🏛 Elsevier Science 🌐 English ⚖ 307 KB

The structure of the silicotitanate CsTiSi 2 O 6.5 has been analyzed with neutron powder and X-ray single crystal diffraction techniques. The compound crystallizes with the symmetry of space group Ia3 d and lattice parameter a ‫؍‬ 13.8417(7) A s . There are 16 formula units in the unit cell. The bas

Synthesis, Crystal and Magnetic Structur
Synthesis, Crystal and Magnetic Structure of the Double Perovskites A2NiMoO6 (A = Sr, Ba): A Neutron Diffraction Study
✍ María J. Martínez-Lope; José A. Alonso; María T. Casais 📂 Article 📅 2003 🏛 John Wiley and Sons 🌐 English ⚖ 168 KB 👁 1 views

## Abstract A~2~NiMoO~6~ (A = Sr, Ba) perovskites have been prepared in polycrystalline form by thermal treatment, in air, of previously decomposed citrate precursors. These materials have been studied by X‐ray (XRD) and neutron powder diffraction (NPD) data. At room temperature, the crystal struct

Temperature-Dependence of the Crystal St
Temperature-Dependence of the Crystal Structure of K2[RuCl5NO]: A Powder Neutron Diffraction Study
✍ M. Rüdlinger; J. Schefer; P. Fischer; N. Furer; H.U. Güdel 📂 Article 📅 1993 🏛 Elsevier Science 🌐 English ⚖ 167 KB

A powder neutron diffraction study of the crystal structure of \(\left.\mathrm{K}_{2} \mid \mathrm{RuCl}_{s} \mathrm{NO}\right)\) in the electronic groundstate is presented in the temperature range from 25 to \(295 \mathrm{~K}\), confirming the orthorhombic space group Prma. Neither a structural nor