Ionic ferromagnetic

ORGANIC INTERCALATED IONIC FERROMAGNETS OF CHROMIUM(II) BIS(ALKYLAMMONIUM) TETRACHLOROCHROMATE(II) COMPOUNDS... 

Bellitto. C. Day, P. Wood, T.E. Magnetic susceptibilities and optical study of the organic-intercalated two-dimensional ionic ferromagnet bis (benzyl ammonium)tetrachor-ochromate(II). J. Chem. Soc. Dalton Trans. 1986, 847. 

The fully ionic solids (region I) afforded band insulators, 1 1 Mott insulators with ground states of antiferromagnets (E b(21) and F b(22) in Fig. 1) or spin-Peierls systems, ferroelectrics, ferromagnets, spin-ladders, and nonlinear transport materials (switching and memory). 

FERROELECTRIC EFFECT. The phenomenon whereby certain crystals may exhibit a spontaneous dipole moment twhich is called ferroelectric by analogy with ferromagnetic—exhibiting a permanent magnetic moment). The effect in the most typical case, barium manate. seems to he due to a polarization catastrophe, in which the local electric fields due lo the polarizuiion itself increase faster than die elastic restoring forces on the ions in Ihe crystal, thereby leading to an asymmetrical shift in ionic positions, and hence lo a permanent dipole moment. Ferroelectric crystals... 

The Hamiltonian (480) of orientational oscillations of ionic groups in the hydrogen-bonded chain can be related to the model of easy-axis ferromagnetic in transversal external field 2Trot. The Hamiltonian (480) resembles the Hamiltonian (451) in outward appearance, and this means that we can reduce the problem to the previous one. However, we are interested in the explicit form of parameters Or<)l and UIot. For this purpose we should start from the appropriate classical Hamiltonian that describes the motion of an oriental defect in the hydrogen bonded chain [325] ... 

We discuss classical non-ideal liquids before treating solids. The strongly interacting fluid systems of interest are hard spheres characterized by their harsh repulsions, atoms and molecules with dispersion interactions responsible for the liquid-vapour transitions of the rare gases, ionic systems including strong and weak electrolytes, simple and not quite so simple polar fluids like water. The solid phase systems discussed are ferromagnets and alloys. 

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