  Boron (B) sheet has been intently studied and various candidates with
vacancies have been proposed by theoretical investigations, including the
possible growth on metal surface. However, a recent experiment (Science 350,
1513, 2015) reported that the sheet formed on the Ag(111) surface was a buckled
triangular lattice without vacancy. Our calculations combined with
High-Throughput screening and the first-principles method demonstrate a novel
growth mechanism of boron sheet from clusters, ribbons, to monolayers, where
the B-Ag interaction is dominant in the nucleation of boron nanostructures. We
have found that the simulated STM image of the sheet with 1/6 vacancies in a
stripe pattern is in better agreement with the experimental observation, which
is energetically favored during the nucleation and growth.
