title: Cagelike diamondoid nitrogen at high pressures.
abstract: Under high pressure, triply bonded molecular nitrogen dissociates into singly bonded polymeric nitrogen, a potential high-energy-density material. The discovery of stable high-pressure forms of polymeric nitrogen is of great interest. We report the striking stabilization of cagelike diamondoid nitrogen at high pressures predicted by first-principles structural searches. The diamondoid structure of polymeric nitrogen has not been seen in any other elements, and it adopts a highly symmetric body-centered cubic structure with lattice sites occupied by diamondoids, each of which consists of ten nitrogen atoms, forming a N(10) tetracyclic cage. Diamondoid nitrogen possesses a wide energy gap and is energetically most stable among all known polymeric structures above 263 GPa, a pressure that is accessible to a high-pressure experiment. Our findings represent a significant step toward the understanding of the behavior of solid nitrogen at extreme conditions.
authors.affiliation: Institute of Condensed Matter Physics, Linyi University, Linyi 276005, People's Republic of China.
authors.forename: Xiaoli
authors.initials: X
authors.lastname: Wang
authors.forename: Yanchao
authors.initials: Y
authors.lastname: Wang
authors.forename: Maosheng
authors.initials: M
authors.lastname: Miao
authors.forename: Xin
authors.initials: X
authors.lastname: Zhong
authors.forename: Jian
authors.initials: J
authors.lastname: Lv
authors.forename: Tian
authors.initials: T
authors.lastname: Cui
authors.forename: Jianfu
authors.initials: J
authors.lastname: Li
authors.forename: Li
authors.initials: L
authors.lastname: Chen
authors.forename: Chris J
authors.initials: CJ
authors.lastname: Pickard
authors.forename: Yanming
authors.initials: Y
authors.lastname: Ma