Glass behavior

J. Koch, C.J.W. (1983) A new interpretation of Mossbauer spectra of microcrystalline goethite super-ferromagnetic" or superspin-glass" behavior J. Magn. Mag. Mat. 40 163-174... 

Feng, X., Cunnane, J. C. Bates, J. K. 1994. A literature review of surface alteration layer effects on waste glass behavior. Ceramics Transactions, 39, 341-352. 

AC susceptibility measurements are frequently used to identify thermodynamic phase transitions and to characterize spin-glass behavior and superparamagnets such as the single-molecule magnets discussed below. 

These considerations lead us to propose the tentative phase diagram of fig. 28. The orthorhombic-rhombohedral transition has been tracked by Wold and Arnott (1959). The two-phase region 0.05 < 5 < 0.10 observed by room-temperature X-ray diffraction has been shown from the spin-glass behavior below 7 to extend over a wider compositional range below 200 K, which indicates that a spinodal phase segregation separates the O -orthorhombic (c/a < x/2) from an O -orthorhombic (c/a J2) or R-rhombohedral phase. With neutron powder diffraction, Huang et al. (1997) have shown the two-phase region at 300 Kin the inter-... 

Phase Separation. The formation of FM clusters in an AFM host matrix in the rare earth manganates has been noticed by many workers. Thus, spin glass behavior has been encountered in the Lni-jArMnOj system at either extreme, corresponding to large or small x. Electronic phase separation is also evidenced... 

Kundu, A. K, Nordblad, P. Rao, C. N. R, 2006 Spin-glass behavior in Pr0.7Cao.3CoO3 and Ndo.7Cao.3Co03. J. Solid State Chem. 179, 923-927. (doi 10.10l6/j.jssc,2005,12.014)... 

While some disordered magnetic systems do display spin-glass behavior, those that are not geometrically frustrated can behave in a fundamentally different way. In... 

Rancourt DG, Lamarche G, Tume P, Lalonde AE, Biensan P, Flandrois S (1990b) Dipole-dipole interactions as the source of spin-glass behavior in exchangewise two-dimensional ferromagnetic layer compounds. Canadian J Phys 68 1134-1137... 

Polystyrene fractions. Numerical data for the PS reference fractions are summarized in Table III Cp(T) curves are not shown, as they resemble the conventional glass behavior illustrated on Figure 2. 

The above discussion does not explain why in certain experiments the coupling between Mn atoms exhibits antiferromagnetism or spin glass behavior. We note that most of these experiments involve thin films. It is, therefore, important to understand if the magnetic behavior of Mn on surfaces and in thin films is fundamentally different from that in the bulk. For example, do Mn atoms prefer to reside on the surface, do they prefer to cluster, and does the Mn-Mn distance depend upon the crystallographic orientation of the surface In the following we discuss these aspects. 

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