To overcome the limitations of graphene due to lack of intrinsic band gap, it is generally functionalized with hydrogen or halogen atoms such as fluorine and chlorine. Generally, such functionalization yields a moderate- to high-band-gap material in case of 100% coverage, for example ~1.5 eV in graphene functionalized with chlorine atoms or chlorographene. In this paper, using ab initio calculations, we report very interesting transformations observed in chlorographene under external strain, driving it to a state with nearly vanishing band gap (under tensile strain) and even converting it to a metal (under compressive strain). We also show the importance of spin-orbit coupling, responsible for the few meV band gap of chlorographene observed under high tensile strain, which would have been a gapless semimetal otherwise.
@article{arxiv.1808.03431,
title = {External-strain-induced semimetallic and metallic phase of chlorographene},
author = {Shivam Puri and Somnath Bhowmick},
journal= {arXiv preprint arXiv:1808.03431},
year = {2018}
}