Infrared Absorption Characteristics of Solid Nitrogen at Near-Triple Point Temperatures

The smooth, uniform, and transparent solid nitrogen-molecular film was grown by applying the slow thermal cycles near the triple-point temperature to the growth process in our home-made liquid/solid preparation apparatus. The infrared absorption spectra of solid nitrogen at near-triple point temperature are measured by the infrared spectroscopy system. A broad absorption band can be observed from 2222 to 2439 cm?1 with the strongest peak at 2288 cm?1. This has been well explained theoretically on the basis of the ground-state vibration and the coupling between the ground-state vibration and rotation at low temperatures within the framework of anharmonic approximation.