
TY  - JOUR
A1  - Collins, JG 
A1  - Collocott, SJ 
A1  - Tainsh, RJ 
A1  - Andrikidis, C 
A1  - White, GK 
T1  - Low Temperature Heat Capacity and Thermal Expansion of KCI Containing a Low Concentration of Li+
JF  - Australian Journal of Physics
JO  - Aust. J.  Phys.
Y1  - 1987
VL  - 40
IS  - 1
SP  - 65
EP  - 72
KW  - 
UR  - https://doi.org/10.1071/PH870065 
N2  - The linear thermal expansion coefficient a from 180 mK to 36 K and the heat capacity per gram cp from 0·5 to 10 Kare reported for KCl containing approximately 100 ppm Li+. Contributions to a and cp attributable to the impurity have been identified and analysed on the basis of a model in which the Li + ions reside about 0·05 nm from the equilibrium cationic site in any of the (111) directions. There is consistent quantitative agreement with a Schottky-like term that arises from the eightfold degeneracy of the level splitting; the splitting parameter is 1· 5 K. The large (- 160) Grtineisen parameter associated with the impurity contribution is evidence for a quantum-mechanical tunnelling process, and agrees with values derived from independent measurements of the spectroscopic and dielectric responses of this system under pressure. 
ER  -

