title: Quasiparticle electronic structure and optical absorption of diamond nanoparticles from ab initio many-body perturbation theory.
abstract: The excited states of small-diameter diamond nanoparticles in the gas phase are studied using the GW method and Bethe-Salpeter equation (BSE) within the ab initio many-body perturbation theory. The calculated ionization potentials and optical gaps are in agreement with experimental results, with the average error about 0.2 eV. The electron affinity is negative and the lowest unoccupied molecular orbital is rather delocalized. Precise determination of the electron affinity requires one to take the off-diagonal matrix elements of the self-energy operator into account in the GW calculation. BSE calculations predict a large exciton binding energy which is an order of magnitude larger than that in the bulk diamond.
authors.affiliation: School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, China.
authors.forename: Huabing
authors.initials: H
authors.lastname: Yin
authors.affiliation: School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, China.
authors.forename: Yuchen
authors.initials: Y
authors.lastname: Ma
authors.affiliation: School of Physics, State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, China.
authors.forename: Xiaotao
authors.initials: X
authors.lastname: Hao
authors.affiliation: School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, China.
authors.forename: Jinglin
authors.initials: J
authors.lastname: Mu
authors.affiliation: School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, China.
authors.forename: Chengbu
authors.initials: C
authors.lastname: Liu
authors.affiliation: Department of Physics, China University of Mining and Technology, Xuzhou 221116, China.
authors.forename: Zhijun
authors.initials: Z
authors.lastname: Yi