Carbon nitride frameworks and dense crystalline polymorphs
Document Type
Article
Publication Date
1-1-2016
Publication Title
Physical Review B
Volume
94
Issue
9
Abstract
We used ab initio random structure searching (AIRSS) to investigate polymorphism in C3N4 carbon nitride as a function of pressure. Our calculations reveal new framework structures, including a particularly stable chiral polymorph of space group P43212 containing mixed sp2 and sp3 bonding, that we have produced experimentally and recovered to ambient conditions. As pressure is increased a sequence of structures with fully sp3-bonded C atoms and three-fold-coordinated N atoms is predicted, culminating in a dense Pnma phase above 250 GPa. Beyond 650 GPa we find that C3N4 becomes unstable to decomposition into diamond and pyrite-structured CN2. © 2016 American Physical Society.
Language
English
Repository Citation
Pickard, C. J.,
Salamat, A.,
Bojdys, M. J.,
Needs, R. J.,
McMillan, P. F.
(2016).
Carbon nitride frameworks and dense crystalline polymorphs.
Physical Review B, 94(9),
http://dx.doi.org/10.1103/PhysRevB.94.094104