Magnetic susceptibility data, plots

Fig. 2 Curie-Weiss jX versus T (left), /T versus T (middle), and X versus T (right) plots of magnetic susceptibility data. In the middle plot, a diamagnetic sample shows a negative response.

The magnetic susceptibility data of the compound are represented in Fig. 4 in the form of the X T vs T plot, being the molar magnetic susceptibility and T the temperature. The curve exhibits a rounded minimum around 100 K. 

The values of C and 0 are usually determined graphically from the straight line which fits best to the experimental 1/xm data plotted versus temperature (Curie-Weiss plot). The TIP contribution may be also obtained graphically if the molar magnetic susceptibility is plotted as function of 1/T and extrapolated for l/T- 0. Often No. is incorporated into Eq. (27), its numerical value being estimated on the basis of ligand field theory [22,45]. For methods to determine Na empirically, cf. [46,47]. 

Magnetic susceptibility data are usually represented by a plot of 1/xm vs T. This plot is linear over a particular range of temperatures, and the data are fitted to the... 

Fig. II. (a) Temperature dependence of the magnetization for 200-nm thick Ga, MnrAs with x =0.053. The magnetic field is applied perpendicular to the sample surface (hard axis). The inset shows the temperature dependence of the remanent magnetization (0 T) and the magnetization at 1 T in a field parallel to the film surface, (b) Temperature dependence of the saturation magnetization determined from the data shown in (a) by using ArTott plots (closed circles). Open circles show inverse magnetic susceptibility and the Curie-Weiss fit is depicted by the solid straight line (Ohno and Matsukura 2001).

Magnetic Susceptibility of TiNi has been previously observed [39] to be temperature independent and interpreted as due to Pauli spin susceptibility. This categorizes the magnetic property as one that is insensitive to the atomic arrangement. The magnetic susceptibility has the constant values, 2.1 x 10 6 (emu/g) below the Ms and 3.0 x 10"6 (emu/g) above the As temperature. Between these two temperatures a plot of the data has a triangular form but as predicted, no difference is observed between those obtained from complete and incomplete cycles. 

Magnetic susceptibilities of 10a and 10b were measured on a SQUID suscep-tometer in microcrystalline form. %T-T plots are shown in Fig. 9.5. The data were analyzed in terms of a modified singlet-triplet two-spin model (the Blea-ney-Bowers-type), in which two spins (S = V2) couple antiferromagnetically within a biradical molecule by exchange interaction J. The best-fit parameters obtained by means of a least-squares method were 2J/kB = -2.2 + 0.04 K for 10a and -11.6 + 0.4 K for 10b. Although the interaction (2J/kB = -2.2 K) between the two spins in the open-ring isomer 10a was weak, the spins of 10b showed a remarkable antiferromagnetic interaction (2J/kB = -11.6 K). 

The molar magnetic susceptibility, xm, which has been corrected for the diamagnetism of the constituent atoms, is plotted versus If a straight line is obtained, then the data follow the Curie law, x = C jT. The effective magnetic moment is given by... 

Figure9.10 AC susceptibility data for [Gd2(TCNQ)5(H20)9][Gd(TCNQ)4 (H20)3] -4H20, in-phase (empty circle), out-of-phase (solid square). Inset plot of M-H performed at 1.8 K [86]. (Reprinted with permission from H. Zhao, et al., A rare-earth metal TCNQ magnet synthesis, structure, and magnetic properties of [Gd2(TCNQ)5(H20)9][Gd(TCNQ)4(H20)3] 4H20, Angewaru/te Chemie International Edition, 2003, 42, 1015-1018 (Figure 2). Wiley-VCH Verlag GmbH Co. KGaA.)...

The electrical resistivity and magnetic susceptibility of these samples were measured as functions of temperature and the results are plotted in Figures 9 and 10. As can be seen from Figure 9, the resistivity data defines an extremely sharp transition at a temperature of 92 K. The superconducting nature of the compound below this temperature is verified by the Meissner effect evident in the susceptibility data shown in Figure 10. 

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