Two-dimensional(2 D)materials with honeycomb,kagome or star lattice have been intensively studied because electrons in such lattices could give rise to exotic quantum effects.In order to improve structural diversity o...Two-dimensional(2 D)materials with honeycomb,kagome or star lattice have been intensively studied because electrons in such lattices could give rise to exotic quantum effects.In order to improve structural diversity of 2 D materials to achieve unique properties,here we propose a new quasi-2 D honeycombstar-honeycomb(HSH)lattice based on first-principles calculations.A carbon allotrope named HSH-C_(10) is designed with the HSH lattice,and its mechanical properties have been intensively investigated through total energy,phonon dispersion,ab initio molecular dynamic simulations,as well as elastic constants calculations.Besides the classical covalent bonds,there is an interesting charge-shift bond in this material from the chemical bonding analysis.Additionally,through the analysis of electronic structure,HSH-C_(10) is predicted to be a semiconductor with a direct band gap of 2.89 e V,which could combine the desirable characteristics of honeycomb and star lattice.Importantly,by modulating coupling strength,a flat band near the Fermi level can be obtained in compounds HSH-C_(6)Si_(4) and HSH-C_(6)Ge_(4),which have potential applications in superconductivity.Insight into such mixed lattice would inspire new materials with properties we have yet to imagine.展开更多
基金partially supported by the National Natural Science Foundation of China(Nos.21773124,12134019)by the Fundamental Research Funds for the Central Universities(Nankai University,No.63213042)+3 种基金by the Ph.D.Candidate Research Innovation Fund of Nankai UniversityScience and Technology Research Project of Hubei Provincial Department of Education(No.D20212603)Hubei University of Arts and Science(Nos.2020kypytd001,2020kypytd002,XK2021024)supported by the Supercomputing Center of Nankai University(NKSC)。
文摘Two-dimensional(2 D)materials with honeycomb,kagome or star lattice have been intensively studied because electrons in such lattices could give rise to exotic quantum effects.In order to improve structural diversity of 2 D materials to achieve unique properties,here we propose a new quasi-2 D honeycombstar-honeycomb(HSH)lattice based on first-principles calculations.A carbon allotrope named HSH-C_(10) is designed with the HSH lattice,and its mechanical properties have been intensively investigated through total energy,phonon dispersion,ab initio molecular dynamic simulations,as well as elastic constants calculations.Besides the classical covalent bonds,there is an interesting charge-shift bond in this material from the chemical bonding analysis.Additionally,through the analysis of electronic structure,HSH-C_(10) is predicted to be a semiconductor with a direct band gap of 2.89 e V,which could combine the desirable characteristics of honeycomb and star lattice.Importantly,by modulating coupling strength,a flat band near the Fermi level can be obtained in compounds HSH-C_(6)Si_(4) and HSH-C_(6)Ge_(4),which have potential applications in superconductivity.Insight into such mixed lattice would inspire new materials with properties we have yet to imagine.
