High-temperature infrared spectroscopy of YCl 3: the vibration spectrum, molecular structure and thermodynamic functions

Abstract

The infrared spectrum of gaseous YCl 3 has been measured at 1400 K and three absorption bands have been found in the 50–600 cm −1 range. Based on a comparison with LaCl 3, of which the spectrum was also recorded, it is concluded that the absorption maximum at 370 cm −1 is an overlap of the two stretching frequencies of a pyramidal structure. By spectral deconvolution, the absorption bands could be separated, resulting in the following vibrational assignments: ν 1 = 378; ν 2 = 78; ν 3 = 359; ν 4 = 58.6 cm −1. From these data the ideal gas thermodynamic functions have been calculated.