EPR study of the onset of long-range order in the 2D organo-metallic magnet Cu(pyz)2(pyo)2(PF6)2
- Los Alamos National Laboratory
- OXFORD
- EWU
The spin (S) 1/2 two-dimensional (2D) square-lattice quantum Heisenberg antiferromagnet system has long been interesting to theoretical physicists due to the variety of transitions that can arise. Moreover, the role of S = 1/2 fluctuations on a square lattice in the mechanism for cuprate superconductivity is hotly debated. Low dimensional metal-organic magnets, such as Cu(pyz){sub 2}(pyo){sub 2}(PF{sub 6}){sub 2}, offer the possibility to readily control the exchange parameters in a 20 system by changing chemical composition, thus creating spin architectures with desirable properties 'to order'. For a perfectly 20 system, long range magnetic order would not occur at finite temperature. However, in the metal-organic systems, interlayer coupling gives rise to a finite Neel temperature. For these quasi-2D systems the ordering temperature is dominated by the weakest (the interlayer) exchange interaction, whereas the saturation magnetic field is dominated by the strongest exchange interactions, thus providing a means of estimating the spatial exchange anisotropy in the system. It should be noted that the more 2D the system, the wider the temperature (T) range, T{sub N} < T < J/k{sub B}, over which magnetic fluctuations dominate. As evident by the ratio of magnetic saturation field, H{sub sat} {approx} 30 T, to the Neel temperature, T{sub N} = 1.72 K, Cu(pyz){sub 2}(pyo){sub 2}(PF{sub 6}){sub 2} is a good example of a 2D system with the anisotropy between inplane and interplane exchange interactions being of the order of 10{sup 3}.
- Research Organization:
- Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
- Sponsoring Organization:
- USDOE
- DOE Contract Number:
- AC52-06NA25396
- OSTI ID:
- 1047131
- Report Number(s):
- LA-UR-11-00331; LA-UR-11-331; TRN: US1203862
- Country of Publication:
- United States
- Language:
- English
Similar Records
Structural Electronic and Magnetic Properties of Quasi-1D Quantum Magnets [Ni(HF2)(pyz)2]X (pyz = pyrazine; X = PF6- SbF6-) Exhibiting Ni-FHF-Ni and Ni-pyz-Ni Spin Interactions
Antiferromagnetism in a Family of S = 1 Square Lattice Coordination Polymers NiX 2 (pyz) 2 (X = Cl, Br, I, NCS; pyz = Pyrazine)