High-pressure new phase of AgN3

Abstract

The structural evolutionary behaviors of AgN3 have been studied by using the particle swarm optimization structure search method combined with the density functional theory. One stable high-pressure metal polymeric phase with the [Formula: see text] space group is suggested. The enthalpy difference analysis indicates that the Ibam-AgN3 phase will transfer to the I4/mcm-AgN3 phase at 4.7 GPa and then to the [Formula: see text]-AgN3 phase at 24 GPa. The [Formula: see text]-AgN3 structure is composed of armchair–antiarmchair N-chain, in which all the N atoms are sp2 hybridization. The inherent stability of the armchair–antiarmchair chain and the anion–cation interaction between the N-chain and Ag atom induce a high stability of the [Formula: see text]-AgN3 phase, which can be captured at ambient conditions and hold its stable structure up to 1400 K. The exhibited high energy density (1.88 KJ/g) and prominent detonation properties ([Formula: see text] Km/s; [Formula: see text] GPa) of the [Formula: see text]-AgN3 phase make it a potentially high energy density material.