title: Π-Bond maximization of graphene in hydrogen addition reactions.
abstract: Thermodynamic stability of graphene hydrides increases in an approximately linear way with the numbers of π-bonds they contain. Thus, π-bond maximization is the primary driving force for hydrogen addition reactions of graphene. The previously reported thermal preference of sp(2)/sp(3)-phase separation of graphene hydrides is a straightforward effect of π-bond maximization. Although not well applicable to hydroxylation and epoxidation, the π-bond maximization principle also holds approximately for the fluorination reactions of graphene. The findings can be used to help locate the lowest-energy structures for graphene hydrides and to estimate the hydrogenation energy without first-principles calculations.
authors.affiliation: Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, China. gaox@ihep.ac.cn
authors.forename: Xingfa
authors.initials: X
authors.lastname: Gao
authors.forename: Yuliang
authors.initials: Y
authors.lastname: Zhao
authors.forename: Bo
authors.initials: B
authors.lastname: Liu
authors.forename: Hongjun
authors.initials: H
authors.lastname: Xiang
authors.forename: Shengbai B
authors.initials: SB
authors.lastname: Zhang