Observation of Spin Relaxation in a Vanadate Chloride with Quasi-One-Dimensional Linear Chain

• Published in: Crystal growth & design 2019-04, Vol.19 (4), p.2228-2234
• Main Authors: Zhang, Su-Yun, Guo, Wen-Bin, Tang, Ying-Ying, Xu, Jin-Qiu, He, Zhang-Zhen
• Format: Article
• Language: English
• ISSN: 1528-7483; 1528-7505
• DOI: 10.1021/acs.cgd.8b01839

A new cobalt­(II) vanadate chloride, Pb2Co­(OH)­(V2O7)­Cl, has been synthesized under mild hydrothermal conditions. It contains quasi-one-dimensional (1D) linear chains built by edge-sharing of CoIIO6 octahedra. The cobalt­(II) oxide chains are further interconnected by (V2O7)4– dimers into a three-dimensional (3D) anionic framework with Pb2+ and Cl– ions residing in Co4V8 12-member ring tunnels. The intrachain Co···Co distance is 3.041 Å, while the interchain distances are 8.742 and 9.256 Å. Magnetic measurements suggest the ferromagnetic intrachain and the antiferromagnetic interchain interactions with a specific value of J intra/J inter = 1.7 × 103. Zero-field heat capacity demonstrates the magnetic long-range ordering at 5.5 K. Alternating current (AC) magnetic susceptibility under zero external direct current (DC) fields displays two slow magnetic relaxations at low temperatures, giving characteristic relaxations (τ0) of 1.2(3) × 10–12 and 1.9(4) × 10–10 s with effective energy barriers (Δτ) of 76.1(2) and 48.4(5) K. The energy barrier between the spin up and spin-down states can be ascribed to the ferromagnetic spin chain and the Ising-like magnetic anisotropy in Pb2Co­(OH)­(V2O7)­Cl.