Carbon nitride frameworks and dense crystalline polymorphs
Accepted version
Peer-reviewed
Repository URI
Repository DOI
Change log
Authors
Pickard, CJ
Salamat, A
Bojdys, MJ
Needs, RJ
McMillan, PF
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.
Description
Keywords
cond-mat.mtrl-sci, cond-mat.mtrl-sci
Journal Title
Physical Review B
Conference Name
Journal ISSN
2469-9950
2469-9969
2469-9969
Volume Title
94
Publisher
American Physical Society (APS)
Publisher DOI
Sponsorship
Engineering and Physical Sciences Research Council (EP/J017639/1)
Engineering and Physical Sciences Research Council (EP/K014560/1)
Engineering and Physical Sciences Research Council (EP/K014560/1)
Engineering and Physical Sciences Research Council (EPSRC) (Grant IDs: EP/J017639/1, EP/G007489/2, EP/K013688/1, EP/K014560/1, EP/L01709/1), Royal Society (Wolfson Research Merit Award), Czech Science Foundation (Junior Grant (CAMs – 16-21151Y)), European Research Council (Starting Grant scheme (BEGMAT – 678462))