Characterization of interaction energy and vibrational Raman spectra of nitrogen clathrate hydrates

Abstract

Nitrogen clathrate hydrates are caged compounds where nitrogen molecules are encapsulated in dodecahedron (512) and hexakaidecahedron (51264) water cages. In the present work, we characterize the interaction energy and vibrational Raman spectra of multiple occupancy of N2 in 512 and 51264 water cages using Density Functional Theory. The interaction energies shows that 512(N2) and 51264(N2)2 cages to be the most stable, which is consistent with experimental observations. The spectral shifts suggest the 512(N2) and 51264(N2)2 cages are more stable compared to the 512(N2)2 and 51264(N2)n=1,3 cages respectively which corroborate the trends seen from interaction energies.