“…56 For a-PbO and b-PbO the (001) and (100) surfaces, respectively, which arise due to the breaking of weak van der Waals interactions between the layers, were found to be the most stable, in agreement with previous reports (on isostructural SnO) 57 and b-PbO. 53 For b-PbO 2 and SnO 2 , the (110) surface was deduced to be the most stable, in agreement with other DFT calculations reported for isostructural rutile TiO 2 , [58][59][60] which has also been verified experimentally. 61 Due to breaking of Pb-O bonds, b-PbO 2 (110) has a noticeably higher surface energy for formation compared to the other lead systems.…”