Heat capacity anomalous

Water is well known to have an unusually high heat capacity. Not so well known is that liquid XeFA also has a high heat capacity compared to "normal" liquids such as argon, carbon tetrachloride, or sulfur dioxide. From your knowledge of the structures of the solids and the gaseous molecules of these materials (most of them are sketched in this text), explain the "anomalous heat capacity of XeF . 

Gill SJ, Dec SF, Olofsson G, Wadsd I. Anomalous heat-capacity of hydrophobic solvation. J. Phys. Chem. 1985 89 3758-3761. Muller N. Search for a realistic view of hydrophobic effects. Acc. Chem. Res. 1990 23 23-28. 

Frank, H. S., Evans, M. W. (1945). Free volume and entropy in condensed systems. Journal of Chemical Physics, 13, 507-532. Gill, S. J., Dec, S. F., Olofsson, G., Wadso, I. (1985). Anomalous heat capacity of hydrophobic solvation. Journal of Physical Chemistry, 89, 3758-3761. 

CeAl3 is a very interesting case where the superposition of the Kondo effect on crystal field interaction gives rise to anomalous heat capacity (7(5) and resistivity behavior (46, 77, 78) at low temperatures. The heat capacity measurements of Mahoney (75) showed that the full entropy of R In 6 was recovered under the excess... 

Rasmussen, D.H., MacKenzie, A.P., Angell, C.A. and Tucker, J.C. (1973) Anomalous heat capacities of supercooled water and heavy wdXer,Science 181,342. 

The explanation of the hydrogen atom spectmm and the photoelectric effect, together with other anomalous observations such as the behaviour of the molar heat capacity Q of a solid at temperatures close to 0 K and the frequency distribution of black body radiation, originated with Planck. In 1900 he proposed that the microscopic oscillators, of which a black body is made up, have an oscillation frequency v related to the energy E of the emitted radiation by... 

The semiconducting properties of the compounds of the SbSI type (see Table XXVIII) were predicted by Mooser and Pearson in 1958 228). They were first confirmed for SbSI, for which photoconductivity was found in 1960 243). The breakthrough was the observation of fer-roelectricity in this material 117) and other SbSI type compounds 244 see Table XXIX), in addition to phase transitions 184), nonlinear optical behavior 156), piezoelectric behavior 44), and electromechanical 183) and other properties. These photoconductors exhibit abnormally large temperature-coefficients for their band gaps they are strongly piezoelectric. Some are ferroelectric (see Table XXIX). They have anomalous electrooptic and optomechanical properties, namely, elongation or contraction under illumination. As already mentioned, these fields cannot be treated in any detail in this review for those interested in ferroelectricity, review articles 224, 352) are mentioned. The heat capacity of SbSI has been measured from - 180 to -l- 40°C and, from these data, the excess entropy of the ferro-paraelectric transition... 

To complete the discussion of the second-order interaction between tunneling centers, we note that the corresponding contribution to the heat capacity in the leading low T term comes from the ripplon-TLS term and scales as 7 +2 where a is the anomalous exponent of the specific law. Within the approximation adopted in this section, a = 0. However, it is easily seen that the magnitude of the interaction-induced specific heat is down from the two-level system value by a factor of 10(a/ ) ([Pg.188]

Instead, an anomalous trend and an excess heat capacity appear at low temperature in the case of the metallized wafer. 

A recent review of the experimental situation has been given by Honig(1985). It is pointed out that the electrical properties, particularly near to the transition, are very sensitive to purity and specimen preparation, and that much of the extensive experimental work is therefore open to doubt. None the less, the broad features of the behaviour of this material are clear. The history of the so-called Verwey transition in this material goes back to 1926, when Parks and Kelly (1926) detected an anomalous peak near 120 K in the heat capacity of a natural crystal of magnetite. The first detailed investigations were those of Verwey and co-workers (Verwey 1939, Verwey and Haayman 1941, Verwey et al. 1947), who showed that there was a near discontinuity in the conductivity at about 160K. The conductivity as measured by Miles et al. (1957) is shown in Fig. 8.1. 

Tn the critical region of mixtures of two or more components some physical properties such as light scattering, ultrasonic absorption, heat capacity, and viscosity show anomalous behavior. At the critical concentration of a binary system the sound absorption (13, 26), dissymmetry ratio of scattered light (2, 4-7, II, 12, 23), temperature coefficient of the viscosity (8,14,15,18), and the heat capacity (15) show a maximum at the critical temperature, whereas the diffusion coefficient (27, 28) tends to a minimum. Starting from the fluctuation theory and the basic considerations of Omstein and Zemike (25), Debye (3) made the assumption that near the critical point, the work which is necessary to establish a composition fluctuation depends not only on the average square of the amplitude but also on the average square of the local... 

The result for the thermal expansion coefficient, a, which is equal to (dV/dT)/V, is shown in Fig. 13.36 for the cooling and heating process. In the cooling process a decreases gradually from tq to ag. Hysteresis in the volume causes in the subsequent heating process an anomalous effect in the thermal expansion coefficient, depicted by undershoot and overshoot, as also shown in Fig. 13.36. A similar effect occurs in enthalpy H and accordingly in cp, the specific heat capacity, equal to dH/dT. This effect is frequently observed in DSC (Differential Scanning Calorimetry) experiments. 

Mg compound I4/m. Despite what is nearly complete B-site ordering, both materials behave as spin-glass like, although the Ca phase shows many anomalous properties, especially in the heat capacity, including an unprecedented T dependence at low temperatures and a robustness of the heat capacity anomaly to fields as large as 6T. It is not yet clear whether the absence of LRO in these materials is related to quantum spin fluctuations, orbital ordering within the t2g manifold, both, or neither. 

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