A low-energy electron diffraction study was made of the α-SiO2(00•1) surface structure modifications induced by thermal treatments in air. A reconstruction was observed as soon as the air-heating temperature was greater than 600C. The reconstructed mesh area was 84 times greater than the initial one. A preliminary interpretation in relation with the α-β transition phase of quartz occurring at 573C was suggested. In particular, the observed rotation angle (11°) between the initial and the reconstructed surface lattices would be possibly related to the orientation of the triangular Dauphiné domains observed near the transition temperature. A LEED Study of the (0001) α-Quartz Surface Reconstruction. F.Bart, M.Gautier: Surface Science, 1994, 311[1-2], L671-6