Entropy anomalies

In this paper we present results from independent studies on the stage 2 to stage 1 transition area that show some unexpected features (anomalies). The results are obtained by electrochemical impedance spectroscopy (EIS), entropy measurements (AS(x)) and in situ x-ray diffractometry (XRD). The aim is to understand the mechanism of stage transition dealing with the observed anomalies. 

Figure 15 displays specific heat data for itinerant antiferromagnetic Nplr2 ° (Tn = 7 K) while results for NpSn3 ° are presented in Fig. 2, showing the BCS-like specific heat anomaly the entropy change at the transition is almost 0. In the case of Np Ir2, the saturation is less clear bad fitting below Tn is attributed to second phase contamination. 

The anomalies of liquid water become more pronounced when it is supercooled. For example, the volume and entropy fluctuations of liquid water become more pronounced as the temperature decreases. This is in contrast to most other liquids, in which the volume and entropy fluctuations become smaller as the temperature is lowered. Furthermore, the volume and entropy fluctuations in water at less than 4°C are anticorrelated, that is, the increase in volume which occurs when water is cooled results in a decrease in entropy (Debenedetti, 2003). 

The entropies of ionization vary over a wide range with changes in R. Nevertheless current chemical theory has been very successful in relating the strengths of such acids to chemical structure. How can we account for this apparent anomaly ... 

Continuous phase transitions show anomalies in the specific heat and magnetic susceptibility (or magnetization) at or very near Tg. There is, however, no latent heat as in so-called first-order transitions but of course there is a decrease in spin entropy. 

The exceptional rank of water is manifested by its unusual properties compared with most other liquids, the so-called anomalies. These anomalies comprise thermodynamic as well as structural and dynamic properties, especially their pressure and temperature dependence. The key to understanding these properties lies in two competing influences on the local structure the attempt to build low-density tetrahedral structures (with low energy) versus the tendency toward closer packing (with higher entropy) (19). 

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