TY - JOUR
T1 - Unusual Magnetism in a d-Electron Compound Fe(OH)Cl
T2 - A X–Y Stacked-Triangular Antiferromagnet with Characteristic Double-Bridge Bonding, Unquenched Orbital Moment and Coexisting Spin Fluctuations
AU - Zheng, Xu Guang
AU - Bhuiyan, Md Mahbubur Rahman
AU - Yamauchi, Ichihiro
AU - Fujihala, Masayoshi
AU - Sugimoto, Kunihisa
AU - Kawae, Tatsuya
AU - Ishigaki, Toru
N1 - Publisher Copyright:
©2024 Society The Author(s) of Japan.
PY - 2024/1/15
Y1 - 2024/1/15
N2 - Single crystals of triangular-lattice Fe(OH)Cl in orthorhombic structure were synthesized and its magnetism was studied thoroughly using multiple magnetic probes of magnetization, muon spin rotation=relaxation (μSR) and neutron diffraction. Antiferromagnetic transition was found at TN = 13.3 K together with slow dynamics and surprisingly unquenched orbital moments in the paramagnetic state. Residual spin fluctuations coexisting with a long-range order below TN were witnessed in μSR. A coplanar spin structure of propagation vector k ¼ ð0; 0; 0Þ confined within the triangular lattice was revealed by neutron diffraction to have a relatively small frozen moment of 1.96 μB. Ferromagnetic superexchange interactions through a characteristic zig-zag path via ∼90° angled double Fe==O==Fe and double Fe==Cl==Fe bridges counted for this spin arrangement, presenting similarity and contrasting difference to the antiferromagnetic zig-zag path in the S = 1=2 triangular lattice Cu(OH)Cl in monoclinic structure. The obtained value of critical exponent, β = 0.2585(16), in Fe(OD)Cl agrees well with the theoretical value 0.253 ∓ 0.01 in the X–Y frustrated spin model for stacked-triangular antiferromagnet. Experimental evidence all consistently demonstrate the existence of magnetic order with extensive spin fluctuations on a wide range from ∼1 to 10−9–10−12 s. This work presents a unique system for studying geometric frustration on frustrated triangular lattice with unquenched orbital moment.
AB - Single crystals of triangular-lattice Fe(OH)Cl in orthorhombic structure were synthesized and its magnetism was studied thoroughly using multiple magnetic probes of magnetization, muon spin rotation=relaxation (μSR) and neutron diffraction. Antiferromagnetic transition was found at TN = 13.3 K together with slow dynamics and surprisingly unquenched orbital moments in the paramagnetic state. Residual spin fluctuations coexisting with a long-range order below TN were witnessed in μSR. A coplanar spin structure of propagation vector k ¼ ð0; 0; 0Þ confined within the triangular lattice was revealed by neutron diffraction to have a relatively small frozen moment of 1.96 μB. Ferromagnetic superexchange interactions through a characteristic zig-zag path via ∼90° angled double Fe==O==Fe and double Fe==Cl==Fe bridges counted for this spin arrangement, presenting similarity and contrasting difference to the antiferromagnetic zig-zag path in the S = 1=2 triangular lattice Cu(OH)Cl in monoclinic structure. The obtained value of critical exponent, β = 0.2585(16), in Fe(OD)Cl agrees well with the theoretical value 0.253 ∓ 0.01 in the X–Y frustrated spin model for stacked-triangular antiferromagnet. Experimental evidence all consistently demonstrate the existence of magnetic order with extensive spin fluctuations on a wide range from ∼1 to 10−9–10−12 s. This work presents a unique system for studying geometric frustration on frustrated triangular lattice with unquenched orbital moment.
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U2 - 10.7566/JPSJ.93.014704
DO - 10.7566/JPSJ.93.014704
M3 - Article
AN - SCOPUS:85185258777
SN - 0031-9015
VL - 93
JO - journal of the physical society of japan
JF - journal of the physical society of japan
IS - 1
M1 - 014704
ER -