Highhyphen;Temperature Heat Contents and Related Thermodynamic Functions of Eight Rarehyphen;Earth Metals: Sc, Gd, Tb, Dy, Ho, Er, Tm, and Lu

摘要

The highhyphen;temperature heat contents of scandium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, and lutetium were measured from 0deg;C to at least the melting points of these metals. The specific heats, heats of transition, heats of fusion, and related thermodynamic functions were calculated. The smoothed values ofHdeg;Tmdash;Hdeg;298.15, (Hdeg;Tmdash;Hdeg;298.15)/T,Sdeg;T, and minus; (Fdeg;Tmdash;Hdeg;298.15)/Tare tabulated at 100deg; intervals. An examination of the entropies of transition and fusion of all of the measured rarehyphen;earth metals shows that the entropy of the fcc(or hcp)rlarr2;bcc transition depends upon the number of valence electrons and the entropy of fusion decreases with increasing rarehyphen;earthhyphen;metal size. The electronic dependence of the entropy of transformation has also been observed to hold for other metals undergoing similar transformations.