upward

Solid

D Laniel, B Winkler, T Fedotenko, A Pakhomova, S Chariton, V Milman, V Prakapenka, L Dubrovinsky, N Dubrovinskaia, High-Pressure Polymeric Nitrogen Allotrope with the Black Phosphorus Structure, PRL 124, 216001 (2020)

A F Schuch, R L Mills, Crystal Structures of the Three Modifications of Nitrogen 14 and Nitrogen 15 at High Pressure, JCP 52, 6000 (1970) – cif