Curie temperature dependence

Cuprous chlorides, ionization, 9 297 Curie temperature dependence, of paramagnetic species in NMR, 32 15 Curium... 

The measured Curie temperature depends upon the exact composition, defect population and sample microstructure. Literature values vary quite widely. 

W P(C H5)3 204 contains some impurity with Curie temperature dependence [73S9]. 

The exchange energy coefficient M characterizes the energy associated with the (anti)paraHel coupling of the ionic moments. It is direcdy proportional to the Curie temperature T (70). Experimental values have been derived from domain-width observations (69). Also the temperature dependence has been determined. It appears thatM is rather stable up to about 300°C. Because the Curie temperatures and the unit cell dimensions are rather similar, about the same values forM may be expected for BaM and SrM. 

The dielectric stiffness can be expressed as a linear temperature dependence based on the Curie-Weiss law at above the Curie point T. 

Fig. 12. Temperature dependences of the magnetisation one curve typical for ferrimagnetic films, eg, RE-TM or garnets, the other one typical for ferromagnetic Co/Pt multilayers (39). compensation temperature = Curie temperature.

Equivalent hydrostatic pressure Pressure dependence of Curie temperature Change in compressibility Change in specific heat Change in thermal expansion... 

Compressibility and pressure dependence of Curie temperature are directly measured changes in specific heat and thermal expansion are calculated from the Ehrenfest relation. 

Figure 3.8 Anomalous temperature dependence of relative dielectric constant of ferroelectric crystals at the transition temperature (Curie point).

Since niobates and tantalates belong to the octahedral ferroelectric family, fluorine-oxygen substitution has a particular importance in managing ferroelectric properties. Thus, the variation in the Curie temperature of such compounds with the fluorine-oxygen substitution rate depends strongly on the crystalline network, the ferroelectric type and the mutual orientation of the spontaneous polarization vector, metal displacement direction and covalent bond orientation [47]. Hence, complex tantalum and niobium fluoride compounds seem to have potential also as new materials for modem electronic and optical applications. 

A recent theoretical analysis of the temperature dependence of the magnetic response of neutral disorder-induced solitons 69], has revealed that these solitons may explain the low-temperature deviation from Curie behavior that is observed in experiments on Durham /ra/t.y-polyaeetylene [70]. A more stringent test of the theory would involve extending these experiments to even lower temperatures (down to 1 K or lower). 

Magnetic measurements of PuFi, between 4.2 and 300 K are consistent at high temperatures with older measurements (10-12). The large temperature dependent diamagnetism observed earlier was not found. Up to 100 K the susceptibility is nearly temperature independent with a value of X ip 2940 x 10-6 emu. The Curie-Weiss behavior near room temperature indicates population of a higher first excited state. The structure of PuFi, is isomorphic with that of UFi, (13), where two different sets of actinide atoms are 8-fold coordinated by a distorted antiprism. 

Four strongly downshifted signals in each spectrum, between 50 and 110 ppm, were assigned to the four CB protons of the cysteines coordinating the Fe ". The contact shifts of the protons reflect the coordination of cysteine to the Fe " of the antiferromagnetically coupled Fe "-Fe" pair as the cysteine protons sense the spin down orientation of the Fe " (S = ) site. This is supported by the observation that the temperature dependence of the cysteine H" protons (measured between 276 and 308 K) follows Curie behavior (decreasing contact shift with increasing temperature). 

Values relative to the cysteines whose signals have an anti-Curie-type temperature dependence. 

The temperature dependence of the molar susceptibility of a paramagnetic substance follows the Curie-Weiss law (if the magnetic field is not too strong) ... 

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