KOREAN JOURNAL OF CHEMICAL ENGINEERING, cilt.27, sa.1, ss.249-252, 2010 (SCI-Expanded)
The thermal expansivity alpha (p) is related to isothermal compressibility kappa (T) at various pressures for constant temperatures of 254.6, 274 and 297.5 K close to the melting pressure in ammonia solid III. By analyzing the experimental data for kappa (T) according to a power-law formula, a linear variation of alpha (p) with the kappa (T) is established here close to the solid-liquid transition in ammonia. Anomalous behavior of thermal expansivity alpha (p) and the isothermal compressibility kappa (T) near the melting pressure is indicative of the lambda-type transition in ammonia solid III.