Vacancies in the C(100)-(2 x 1) diamond surface layers

Our study provides the results of quantum-chemical calculations of the vacancy defect states on a clean and hydrogenated diamond surface C(1 0 0)-(2 x 1) with their positions varying in the first to sixth surface layers. It was found that the most stable defect is the monovacancy in the third layer under the top bilayer dimer row of the clean surface. The formation energy for this vacancy is 0.55 eV. In the hydrogenated surface, the vacancy in the third layer becomes metastable, the ground state is the vacancy in the topmost surface layer. It is shown that a vacancy in the third layer does not lead to further spontaneous graphitization of the surface. (C) 2017 Elsevier B.V. All rights reserved.