Synthesis and properties of the double perovskites La2NiVO6, La2CoVO6, and La2CoTiO6

✍ Scribed by K.L. Holman; Q. Huang; T. Klimczuk; K. Trzebiatowski; J.W.G. Bos; E. Morosan; J.W. Lynn; R.J. Cava

• Book ID: 104029743
• Publisher: Elsevier Science
• Year: 2007
• Tongue: English
• Weight: 843 KB
• Volume: 180
• Category: Article
• ISSN: 0022-4596
• DOI: 10.1016/j.jssc.2006.09.013

✦ Synopsis

The double perovskites La 2 CoVO 6 , La 2 CoTiO 6 , and La 2 NiVO 6 , are described. Rietveld fitting of neutron and powder X-ray diffraction data show La 2 NiVO 6 and La 2 CoVO 6 to have a disordered arrangement of B-cations whereas La 2 CoTiO 6 shows ordering of the B-cations (with $5% Co/Ti inversion). Curie-Weiss fits to the linear region of the 1/w plots reveal Weiss temperatures of À107, À34.8, and 16.3 K for La 2 CoVO 6 , La 2 CoTiO 6 , and La 2 NiVO 6 , respectively, and magnetic transitions are observed. La 2 CoTiO 6 prepared by our method differs from material prepared by lower-temperature routes. A simple antiferromagnetic spin model is consistent with the data for La 2 CoTiO 6 . These compounds are semiconductors with bandgaps of 0.41 (La 2 CoVO 6 ), 1.02 (La 2 CoTiO 6 ) and 0.45 eV (La 2 NiVO 6 ).