Phonons and metastability in compressed nitrogen

摘要

The metastability of a recently proposed candidate for a polymeric structure of nitrogen is confirmed by using linear response theory to calculate the phonon dispersion throughout the Brillouin zone. It is found that the structure is mechanically stable for pressures below at least 360 GPa. Calculations of Raman and infrared-active phonon frequencies are presented for this metastable phase, and calculations of Raman frequencies for two molecular structures are compared with experimental data.