  The surface structure of phosphorene crystals materials is determined using
surface sensitive dynamical micro-spot low energy electron diffraction
({\mu}LEED) analysis using a high spatial resolution low energy electron
microscopy (LEEM) system. Samples of (\textit{i}) crystalline cleaved black
phosphorus (BP) at 300 K and (\textit{ii}) exfoliated few-layer phosphorene
(FLP) of about 10 nm thicknes, which were annealed at 573 K in vacuum were
studied. In both samples, a significant surface buckling of 0.22 {\AA} and 0.30
{\AA}, respectively, is measured, which is one order of magnitude larger than
previously reported. Using first principle calculations, the presence of
surface vacancies is attributed not only to the surface buckling in BP and FLP,
but also the previously reported intrinsic hole doping of phosphorene
materials.
