Low-dimensional magnetism

The general form of the exchange interaction is given by the expression 

Exchange constants Magnetic dimen- sionality Spin components Spin anisotropy 

In real solids the exact equalities and the vanishing of particular terms as indicated in Table 4.4 do not occur. However, the classification into corresponding quasi types of magnetic systems, as indicated in Table 4.5, may still be valid in terms of accounting for the experimental magnetic behaviour. 

Exchange constants Quasi dimensionality Spin components Quasi system 

Magnetic dimensionality Spin anisotropy Long range order 

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Tofield BC (1975) The Study of Covalency by Magnetic Neutron Scattering. 21 1-87 Trautwein AX, Bill E, Bominaar EL, Winkler H (1991) Iron-Containing Proteins and Related Analogs-Complementary Mossbauer, EPR and Magnetic Susceptibility Studies. 78 1-96 Trautwein AX (1974) Mossbauer-Spectroscopy on Heme Proteins. 20 101-167 Tressaud A, Dance J-M (1982) Relationships Between Structure and Low-Dimensional Magnetism in Fluorides. 52 87-146... 

Tressaud, A., Dance, J.-M. Relationships Between Structure and Low-Dimensional Magnetism in Fluorides. Vol. 52, pp. 87-146. 

The physical properties of low dimensional magnetic materials have attracted the attention of many researchers.3015 Several nickel(II) linear chain complexes have been synthesized and... 

Key words Fourier-transform spectroscopy, low-dimensional magnetics, oxides. 

In this presentation, I shall show that high-resolution Fourier-transform infrared spectroscopy is a useful tool for studying (i) rare-earth containing isulators, low-dimensional magnetics, in particular, and (ii) quasi-one dimensional magnetic systems with the spin-Peierls and related instabilities. 

High-resolution infrared spectroscopy of low- dimensional magnetic oxides 217... 

D. Gatteschi, C. Zanchini Spectral-Structural Correlations in High-Spin Cobalt (II) Complexes. - A. Tressaud, J.-M. Dance Relationships Between Structure and Low-Dimensional Magnetism in Fluorides. - V.KJain, R.Bohra, R.C.Mehrotra Structure and Bonding in Organic Derivatives of Antimony (V). 

Relationships Between Structure and Low-Dimensional Magnetism in Fluorides... 

This article is mainly concerned with the relationships between crystallographic features and the presence of a low-dimensional magnetism in fluorinated materials. Fluorides provide examples for most of the different theoretical models of low-dimensional magnetism and, due to the presence of simple bondings, they can contribute to a better understanding of this type of magnetism. 

In the first two chapters, the different theories explaining low-dimensional magnetic behavior will be briefly considered and also the available techniques. Then, the most important part (Chap. 3) will deal with fluorinated materials showing low-dimensional magnetism in structures characterized by a 3-D crystallographic arrangement of MF6 octahedra, layers, chains and rings. Spin-flop and zero-point spin-reduction will be also considered, since fluorides provide in these domains most of the conclusive examples. 

Recently, the study of EPR line widths for the determination of the spin correlations in the paramagnetic state of low-dimensional magnets has been widely extended on the basis of the pionneering publications of Richards and coworkers36 37). 

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