Large magnetic anisotropy of a decorated spin-chain system KCo(MoO)(OH)

• Published in: Dalton transactions : an international journal of inorganic chemistry Vol. 53; no. 15; pp. 6592 - 66
• Main Authors: Patel, Bhakti K, Ye, Feng, Liyanage, W. L. N. C, Buchanan, C. Charlotte, Gilbert, Dustin A, Kolis, Joseph W, Sanjeewa, Liurukara D
• Format: Journal Article
• Published: 16.04.2024
• ISSN: 1477-9226; 1477-9234
• DOI: 10.1039/d4dt00203b

The magnetic structure of K 2 Co 3 (MoO 4 ) 3 (OH) 2 is studied in detail. The material has a half-sawtooth one-dimensional (1-D) structure containing two unique Co 2+ ions, one in the chain backbone and one on the apex of the sawtooth creating a series of isosceles triangles along the b -axis. These triangles can be a source of magnetic frustration. The ability to grow large single crystals enables detailed magnetic measurements with the crystals oriented in a magnetic field along the respective axes. It has a Curie-Weiss temperature CW of 5.3(2) K with an effective magnetic moment of 4.8(3) μ B /Co. The material is highly anisotropic with a sharp antiferromagnetic ordering transition at 7 K with a metamagnetic transition at 2 kOe. Neutron diffraction was used to determine the magnetic structure and revealed a magnetic structure with canted spins along the backbone of the chain while spins along the sawtooth caps maintained a colinear orientation, arranging antiferromagnetically relative to the backbone spins. The parallel chains arrange antiferromagnetically relative to each other along the c -axis and ferromagnetically along the a -axis. The paper presents the hydrothermal synthesis, magnetic properties, and magnetic structure characterization of K 2 Co 3 (MoO 4 ) 3 (OH) 2 half sawtooth chains.