Our calculations show that of the four BN polytypes, r-BN is the most thermodynamically stable at typical CVD conditions; T = 1400-1800 K and p = 1000-10 000 Pa, see Fig. ). This is supported by experimental studies by Solozhenko et al. The relative thermodynamic stability of the four BN polytypes previously derived from first-principles approach by Yu et al. and Solozhenko et al. suggested c-BN to be the most thermodynamically stable phase at ambient conditions. We attribute this discrepancy to our results to be a consequence of the inclusion of correction factors for long-range van der Waals interactions between the BN sheets in the sp 2 -hybridized polytypes h-BN and r-BN. These corrections were not included in Ref. (30). Furthermore, it has been demonstrated that standard DFT calculations fail to provide an appropriate description of the van der Waals interactions, which is important for explaining the properties, e.g., interlayer distance and binding energy, of layered materials like graphite and h-BN .