Antiferromagnetic order

Cheng H S and Wang L S 1996 Dimer growth, structure transition and antiferromagnetic ordering in small chromium clusters Phys. Rev. Lett. 77 51... 

Viitala E, Merikoski J, Manninen M and Timonen J 1997 Antiferromagnetic order and frustration in small clusters Phys. Rev. B 55 11 541... 

Therefore, the only point at which the symmetry properties of the wave functions are changed by the antiferromagnetic ordering is at the point B. Table 12-5 may be used for the characters, time reversal symmetry, and basis functions of the paramagnetic lattice by setting h = ir/2o. In the antiferromagnetic case we use Table 12-7. 

The hexaborides for which the oxidation state of the metal is 2 -f- are CaB, SrBg, BaB5, EuB, YbB. They are diamagnetic except EuB, which is ferromagnetic (Tc = 12.5 K) . The other rare-earth hexaborides are characterized by the 3-1-oxidation state, except for SmB, in which samarium is in a mixed valence state. They exhibit antiferromagnetic order at low T except LaB, YB and SmB . ... 

An example of magnetic contributions to the specific heat is reported in Fig. 3.9 that shows the specific heat of FeCl24H20, drawn from data of ref. [35,36]. Here the Schottky anomaly, having its maximum at 3K, could be clearly resolved from the lattice specific heat as well as from the sharp peak at 1K, which is due to a transition to antiferromagnetic order (lambda peak). 

Temperature dependence of magnetic susceptibility of the PF6 salt was measured from 300 to 4 K at 5 T [35], The spin susceptibility of this salt gradually decreases from 300 to 50 K. Below 50 K, the susceptibility exhibits a rapid decrease accompanied by anisotropic temperature dependence, which is an indication of the long-range antiferromagnetic ordering. A one-dimensional Heisenberg model is... 

Figure 3.29 Ordered arrays of magnetic dipoles, represented by arrows (a) ferromagnetic ordering, (b) antiferromagnetic ordering, and (c) ferrimagnetic ordering.

Figure 9.10 Antiferromagnetic ordering of magnetic moments on Cu2+ ions (a) the idealized structure of La2Cu04 showing magnetic moments on Cu2+ (b) the ordering in one Cu02 sheet and (c) introduction of holes (Cu3+) and electron hopping destroys the antiferromagnetic array.

Transition, and Antiferromagnetic Ordering of Small Chromium Clusters. 

Miyagawa K, Kawamoto K, Nakazawa Y, Kanoda K (1995) Antiferromagnetic ordering and spin structure in the organic conductor, k-(BEDT-TTF)2Cu[N(CN)2]C1. Phys Rev Lett 75 1174-1177... 

Thus UAs is antiferromagnetic below T = 127 K and a change of antiferromagnetic order occurs at 66 K. Measurements as a function of temperature and crystal orientation in fields up to 150 kOe reveal first strong anisotropy, then the existence of a ferromagnetic phase with (110) easy axis in the temperature range 2 - 66 K and just around Tn (Fig. 6). Similar although not identical behaviour is found in UP ... 

The paramagnetic susceptibility of pure FeAl204 (x = 2) gives a Weiss constant 0 = -144 K and a molar Curie constant (emu) = 3.80 K, somewhat large for high-spin Foa ions with a spin-only moment however, there is no apparent antiferromagnetic ordering of the FeA -ion spins down to 9.5 K, where a peak in the susceptibility has been associated with a local Jahn-Teller distortion about the Fe ions ... 

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