Magic vacancy-numbers in h-BN multivacancies: The first-principles study

The stability of multivacancies in monolayer h-BN is studied by using Density Functional Theory (DFT). We investigate some configurations of the part-of-hexagonal ring (PHR) and B-N pairing vacancies. For PHR vacancies (V-1-V-5), we find that B-rich vacancies are more preferable than N-rich ones, and it is also found that B-N pairing divacancies are more stable than two boron or two nitrogen divacancies. As for B-N pairing multivacancies, based on our calculated dissociation energies, we find that V-6 and V-10 are stable among V-2-V-12, and we predict that V-14 is the next stable configuration. Therefore, we propose that the magic numbers in h-BN multivacancies are 4m + 2 (m = 1, 2, 3), which agree the results of the dangling bond counting model (DBCM).