Structural and magnetic properties of Ba2LuMoO6: a valence bond glass.
We report here the synthesis of the site ordered double perovskite Ba(2)LuMoO(6). Rietveld refinement of room temperature powder x-ray diffraction measurements indicates that it crystallizes in the cubic space group Fm3m, with a = 8.3265(1) Å. Powder neutron diffraction data indicate that, unusually, this cubic symmetry is maintained down to 2 K, with [Formula: see text], Mo(5+) ions situated on the frustrated face-centred cubic lattice. Despite dc-susceptibility measurements showing Curie-Weiss behaviour with strong antiferromagnetic interactions at T ≥ 200 K, there is no evidence of long range magnetic ordering at 2 K. At T ≤ 50 K, susceptibility measurements indicate a loss in moment to ∼18% of the expected value, and there is a corresponding loss in the magnitude of the magnetic exchange. The structural and magnetic properties of this compound are compared with the related compound Ba(2)YMoO(6), which is a valence bond glass.
WestCHEM, Department of Pure and Applied Chemistry, University of Strathclyde, 295 Cathedral Street, Glasgow, G1 1XL, UK.
Fiona C
FC
Coomer
Edmund J
EJ
Cussen
D001464:Barium / Q000737:chemistry*; D017610:Calcium Compounds / Q000737:chemistry*; D018360:Crystallography, X-Ray; D005898:Glass / Q000737:chemistry*; D008187:Lutetium / Q000737:chemistry*; D060328:Magnetic Phenomena; D008956:Models, Chemical; D008982:Molybdenum / Q000737:chemistry*; D033363:Neutron Diffraction; D010087:Oxides / Q000737:chemistry*; D013696:Temperature; D014025:Titanium / Q000737:chemistry*; D014961:X-Ray Diffraction
D017610:Calcium Compounds; D010087:Oxides; C059910:perovskite; D001464:Barium; D008187:Lutetium; D008982:Molybdenum; D014025:Titanium