Ultrasonic relaxation and the vibrational specific heat of liquid sulphur dioxide

Abstract

Measurements have been made of the absorption of ultrasonic waves in liquid sulphur dioxide over the range of frequency from 3 to 45 Mc/s and at temperatures of 0, 25 and 50°C. A pronounced relaxation is found, centred about a frequency of approximately 23 Mc/s; this is associated with the time delay in deactivation of two of the three vibrational modes. The mode which does not participate is that of lowest wave-number which is presumed to be responsible for a relaxation at higher frequencies (of the order of 1500 Mc/s). The results are discussed with reference to dispersion measurements in the gas phase.

A Helmholtz Energy Equation of State for Sulfur Dioxide

“…However, they have incorrect behavior at low temperatures, and Polt’s equation is valid only above 273 K, which is much higher than the triple-point temperature of SO 2 . This work presents a Helmholtz energy equation of state for SO 2 valid over all liquid and gas states, which is based on the available thermodynamic property data [given in refs − ] from the literature.…”