The true corrugation of a h-BN nanomesh layer

Hexagonal boron nitride (h-BN) nanomesh, a two-dimensional insulating monolayer, grown on the (111) surface of rhodium exhibits an intriguing hexagonal corrugation pattern with a lattice constant of 3.2 nm. Despite numerous experimental and theoretical studies, structural details such as the corrugation amplitude have been difficult to determine quantitatively due to the differences in chemical and electronic environments in the strongly bound pore regions and the weakly bound wire regions of the corrugated structure. For reliable results it is important to probe the structure with a method that is intrinsically sensitive to the position of the atomic cores rather than the electron density of states.
In this contribution, we determine the corrugation of h-BN nanomesh from angle- and energy-resolved photoelectron diffraction measurements with chemical state resolution. By combining the results from angle and energy scans and comparing them to multiple-scattering simulations true adsorbate-substrate distance can be measured with high precision, avoiding pitfalls of apparent topography observed in scanning probe techniques.

L. H. de Lima et al., 2D Mater. 7, 035006 (2020)