Magnetic Ordering of Ising Spins on Kagomé Lattice with the 1st and the 2nd Neighbor Interactions

The Cu2+ ions in Cu9Cl2(cpa)6 · nH2O (cpa is the anion of 2-carboxy pentonic acid) form a slightly deformed Kagome lattice with a smaller triangle plaquette in each triangle of a Kagome lattice showing strong frustration. The anomalous features of magnetism are the reduction of the Curie constant below 50 K, fractional saturation even in a field of 38 T, and nonlinear magnetic susceptibility below 5 K. We performed inelastic neutron scattering measurements on powder samples and observed dispersionless scattering around 6.5 meV with a full width of about 8 meV indicating a single-site excitation with E/kB [Formula: see text] 70 K. The scattering is less conspicuous above 50 K. These results are interpreted in terms of the plaquette-ordering model that assumes a 120° arrangement of three moments on each triangular plaquette and a random freezing of the remaining paramagnetic moments below 5 K. PACS No.: 75.10Hk

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Magnetic ordering and fluctuation in Kagome lattice anti-ferromagnets, Fe and Cr jarosites

Canadian Journal of Physics ◽

10.1139/p01-108 ◽

2001 ◽

Vol 79 (11-12) ◽

pp. 1511-1516 ◽

Cited By ~ 10

Author(s):

M Nishiyama ◽

T Morimoto ◽

S Maegawa ◽

T Inami ◽

Y Oka

Keyword(s):

Magnetic Transition ◽

Magnetic Ordering ◽

Exchange Interactions ◽

Lattice Relaxation ◽

Spin Correlation ◽

Spin Lattice Relaxation ◽

Kagome Lattice ◽

Kagomé Lattice ◽

Spin Lattice ◽

High Temperature Expansion

Jarosite family compounds, KFe3(OH)6(SO4)2 (abbreviated to Fe jarosite) and KCr3(OH)6(SO4)2 (Cr jarosite) are typical examples of Heisenberg anti-ferromagnets on the Kagome lattice and have been investigated by means of magnetization and NMR experiments. The susceptibility of Cr jarosite deviates from the CurieWeiss law due to the short-range spin correlation below about 150 K and shows the magnetic transition at 4.2 K, while Fe jarosite has the transition at 65 K. The measured susceptibility fits well with the calculated one on the high-temperature expansion for the Heisenberg anti-ferromagnet on the Kagome lattice. The values of the exchange interactions of Cr jarosite and Fe jarosite are derived to be JCr = 4.9 K and JFe = 23 K, respectively. The 1H-NMR spectra of Fe jarosite suggest that the ordered spin structure is the q = 0 type 120° configuration with +1 chirality. The transition is considered to be caused by a weak single-ion type anisotropy. The spin-lattice relaxation rate, 1/T1, of Fe jarosite in the ordered phase decreases sharply with decreasing temperature and can be well explained by the two-magnon process of spin wave with the anisotropy. PACS No.: 75.25+z

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XXZand Ising spins on the triangular kagome lattice

Physical Review B ◽

10.1103/physrevb.78.024428 ◽

2008 ◽

Vol 78 (2) ◽

Cited By ~ 32

Author(s):

Dao-Xin Yao ◽

Y. L. Loh ◽

E. W. Carlson ◽

Michael Ma

Keyword(s):

Kagome Lattice ◽

Kagomé Lattice ◽

Ising Spins

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Synthesis of a d1 titanium fluoride kagome lattice antiferromagnet

10.26434/chemrxiv.9764924 ◽

2019 ◽

Author(s):

Ningxin Jiang ◽

Arun Ramanathan ◽

John Bacsa ◽

Henry La Pierre

Keyword(s):

Long Range ◽

Structural Phase ◽

Magnetic Ordering ◽

Quantum Spin ◽

Kagome Lattice ◽

Weiss Temperature ◽

Positional Disorder ◽

Kagomé Lattice ◽

Planar Array ◽

Long Range Ordering

The kagome lattice, composed of a planar array of corner-sharing triangles, is one of the most geometrically frustrated lattices. The realization of an S = 1/2 kagome latttice antiferromagnet (KLAF) is of particular interest because it may host an intriguing form of matter, a quantum spin liquid state, which showa long-range entanglement and no magnetic ordering down to 0 K. A few S = 1/2 KLAFs exist, typically based on Cu2+, d9 compounds, though they feature structural imperfections. Herein, we present the synthesis of (CH3NH3)2NaTi3F12, which comprises an S = 1/2 kagome layer that exhibits only one crystallographically distinct Ti3+, d1 site, and one bridging fluoride. A static positional disorder is proposed for the intralayer CH3NH3+. No structural phase transitions were observed from 1.8 K to 523 K. Despite its spin-freezing behavior, other features - including its negative Curie-Weiss temperature and a lack of long-range ordering - imply that this compound is a highly frustrated magnet with unusual magnetic phase behaviors.

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