Transitions magnetic

To further clarify the role of magnetic effects on compressibility, a shock compression experiment was performed on an fee 28.5-at. % Ni sample whose initial temperature was raised to 130°C. As is shown in Table 5.1, the compressibility was found to decrease to a value consistent with the nonmagnetic compressibility. Thus, the sharp change in compressibility, the critical values for the transition, and the magnitudes of the compressibility under the various conditions give a clear demonstration that a second-order magnetic transition has been observed, and we will proceed with a quantitative analysis of the transition. 

An extensive treatment of the thermodynamic properties of second-order phase transitions in magnetic crystals has been given by K. P. Belov, Magnetic Transitions, Consultants Bureau, Enterprises, Inc., New York, 1961. 

Cp.m = aT3 (antiferromagnetic crystals below the magnetic transition temperature if it occurs at low T (4.8)... 

EuIn2P2 magnetic susceptibility shows a clear magnetic transition at about 24 K. In Fig. 11.5 c, magnetic susceptibility as a function of the a, a-h, and c direction were obtained on a plate crystal. The a axis exhibits the largest susceptibility and is the easy magnetization direction. The c axis is the hard magnetization direction. 

Phase transitions Spin and magnetic transitions Dynamic solid-state phenomena Solid-state reactions (e.g., thermolysis, radiolysis)... 

Lelievre-Bema, E., Rouchy, J. and Ballou, R. (1994) Field induced first order magnetic transition and associated volume effect in TbMn2, J. Mag. Mag. Mar., 137, L6-L10. 

The general behaviour of the specific heat near a magnetic transition is illustrated in Fig. 3.6 for MnC03. This carbonate undergoes a paramagnetic to antiferromagnetic transition at 24.9 K as the temperature is lowered. 

Fig. 3.6. Specific heats of MnC03 and CaC03 illustrate the general effect of a magnetic transition. Data from [30], The Neel temperature for MnC03 is 29.4 K [30].

W. E. Hatfield, Magnetic Transition Metal Ions, in Encyclopedia of Inorganic Chemistry, 2nd ed., Wiley, Hoboken, NJ, 2006. 

The Mossbauer eflFect can also be used to measure the magnetic transition temperatures of magnetic materials. In fact, it has some advantages over conventional techniques since no external magnetic field is required for the measurement and one thereby avoids the usual problem of extrapolating to zero Hext- Three techniques are often used to measure magnetic transition temperatures. 

One can measure H as a function of temperature to see where Hx vanishes. If one assumes Hx is proportional to the magnetization, one can fit a Brillouin function through the data and extrapolate to zero Hx to get the magnetic transition temperature. As an example, the Neel temperature of -Fe203 has been determined by this technique [see Figure 1 of Ref. 12]. 

If one plots the area under the absorption curve as a function of temperature for a relatively thick absorber, a sharp discontinuity in the curve will be observed at the magnetic transition temperature—see, for example. Figure 11 of Ref. 35. 

Figure 8.9. The foimation of a Nishizawa Horn from the intersection of a magnetic transition and a miscibility gap (from Nishizawa 1992).

Magnetic transition in pure and Ga doped a-Fe20j. Phys. Lett. 7 177-178 Morrison, S.J. Spangler, R.R. V.S. Tripathi (1995) Adsorption of uranium(VI) on amorphous ferric oxhydroxide at high concentrations of dissolved carbon(lV) and sulfur(VI). 

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