Highly Stable Cooperative Distortion in a Weak Jahn鈥揟eller d2 Cation: Perovskite-Type ScVO3 Obtained by High-Pressure and High-Temperature Transformation from Bixbyite

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• 作者：Elizabeth Castillo-Mart铆nez ; Mario Bieringer ; Shahid P. Shafi ; Lachlan M.D. Cranswick ; Miguel 脕ngel Alario-Franco
• 刊名：Journal of the American Chemical Society
• 出版年：2011
• 出版时间：June 8, 2011
• 年：2011
• 卷：133
• 期：22
• 页码：8552-8563
• 全文大小：1136K
• 年卷期：v.133,no.22(June 8, 2011)
• ISSN：1520-5126

文摘

A novel ScVO₃ perovskite phase has been synthesized at 8 GPa and 1073 K from the cation-disordered bixbyite-type ScVO₃. The new perovskite has orthorhombic symmetry at room temperature, space group Pnma, and lattice parameters a = 5.4006(2) 脜, b = 7.5011(2) 脜, and c = 5.0706(1) 脜 with Sc³⁺ and V³⁺ ions fully ordered on the A and B sites of the perovskite cell. The vanadium oxygen octahedra [V鈥揙₆] display cooperative Jahn鈥揟eller (JT) type distortions, with predominance of the tetragonal Q₃ over the orthorhombic Q₂ JT modes. The orthorhombic perovskite shows Arrhenius-type electrical conductivity and undergoes a transition to triclinic symmetry space group P-1 close to 90 K. Below 60 K, the magnetic moments of the 4 nonequivalent vanadium ions undergo magnetic long-range ordering, resulting in a magnetic superstructure of the perovskite cell with propagation vector (0.5, 0, 0.5). The magnetic moments are confined to the xz plane and establish a close to zigzag antiferromagnetic mode.