TY - JOUR
T1 - Anisotropic Triangular Lattice Realized in Rhenium Oxychlorides A3ReO5Cl2(A = Ba, Sr)
AU - Hirai, Daigorou
AU - Yajima, Takeshi
AU - Nawa, Kazuhiro
AU - Kawamura, Mitsuaki
AU - Hiroi, Zenji
N1 - Funding Information:
This work was financially supported by the Japan Society for the Promotion of Science (JSPS) KAKENHI Grant Numbers JP18K13491, JP18H04308 (J-Physics), and JP19H04688 and by Core-to-Core Program (A) Advanced Research Networks.
Publisher Copyright:
Copyright © 2020 American Chemical Society.
PY - 2020/7/20
Y1 - 2020/7/20
N2 - We report the synthesis, crystal structure, and magnetic properties of the two new quantum antiferromagnets A3ReO5Cl2 (A = Sr, Ba). The crystal structure is isostructural with the mineral pinalite Pb3WO5Cl2, in which the Re6+ ion is square pyramidally coordinated by five oxide atoms and forms an anisotropic triangular lattice (ATL) made of S = 1/2 spins. The magnetic interactions J and J′ in the ATL are estimated from magnetic susceptibilities to be 19.5 (44.9) and 9.2 (19.3) K, respectively, with J′/J = 0.47 (0.43) for A = Ba (Sr). For each compound, the heat capacity at low temperatures shows a large T-linear component with no signature of long-range magnetic order above 2 K, which suggests a gapless spin liquid state of one-dimensional character of the J chains in spite of the significantly large J′ couplings. This is a consequence of one-dimensionalization by geometrical frustration in the ATL magnet; a similar phenomenon has been observed in two compounds with slightly smaller J′/J values: Cs2CuCl4 (J′/J = 0.3) and the related compound Ca3ReO5Cl2 (0.32). Our findings demonstrate that 5d mixed-anion compounds provide a unique opportunity to explore novel quantum magnetism.
AB - We report the synthesis, crystal structure, and magnetic properties of the two new quantum antiferromagnets A3ReO5Cl2 (A = Sr, Ba). The crystal structure is isostructural with the mineral pinalite Pb3WO5Cl2, in which the Re6+ ion is square pyramidally coordinated by five oxide atoms and forms an anisotropic triangular lattice (ATL) made of S = 1/2 spins. The magnetic interactions J and J′ in the ATL are estimated from magnetic susceptibilities to be 19.5 (44.9) and 9.2 (19.3) K, respectively, with J′/J = 0.47 (0.43) for A = Ba (Sr). For each compound, the heat capacity at low temperatures shows a large T-linear component with no signature of long-range magnetic order above 2 K, which suggests a gapless spin liquid state of one-dimensional character of the J chains in spite of the significantly large J′ couplings. This is a consequence of one-dimensionalization by geometrical frustration in the ATL magnet; a similar phenomenon has been observed in two compounds with slightly smaller J′/J values: Cs2CuCl4 (J′/J = 0.3) and the related compound Ca3ReO5Cl2 (0.32). Our findings demonstrate that 5d mixed-anion compounds provide a unique opportunity to explore novel quantum magnetism.
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U2 - 10.1021/acs.inorgchem.0c01187
DO - 10.1021/acs.inorgchem.0c01187
M3 - Article
C2 - 32584564
AN - SCOPUS:85088106442
VL - 59
SP - 10025
EP - 10033
JO - Inorganic Chemistry
JF - Inorganic Chemistry
SN - 0020-1669
IS - 14
ER -