High‐Pressure Synthesis of a Nitrogen‐Rich Inclusion Compound ReN8⋅x N2 with Conjugated Polymeric Nitrogen Chains

• DOI: 10.1002/ange.201805152
• Publication Date: 2018-05-18T09:31:45Z
• Authors: Maxim Bykov; Elena Bykova; Egor Koemets; Timofey Fedotenko; Georgios Aprilis; Konstantin Glazyrin; Hanns‐Peter Liermann; Alena V. Ponomareva; Johan Tidholm; Ferenc Tasnádi; Igor A. Abrikosov; Natalia Dubrovins...; Leonid Dubrovinsky
• Keywords: Inorganic Chemistry; Oorganisk kemi; info:eu-repo/classification/ddc/540; high-energy-density materials; high-pressure chemistry; nitrides; polymeric nitrogen; X-ray diffraction; 540

AbstractA nitrogen‐rich compound, ReN8⋅x N2, was synthesized by a direct reaction between rhenium and nitrogen at high pressure and high temperature in a laser‐heated diamond anvil cell. Single‐crystal X‐ray diffraction revealed that the crystal structure, which is based on the ReN8 framework, has rectangular‐shaped channels that accommodate nitrogen molecules. Thus, despite a very high synthesis pressure, exceeding 100 GPa, ReN8⋅x N2 is an inclusion compound. The amount of trapped nitrogen (x) depends on the synthesis conditions. The polydiazenediyl chains [−N=N−]∞ that constitute the framework have not been previously observed in any compound. Ab initio calculations on ReN8⋅x N2 provide strong support for the experimental results and conclusions.