 Gerber and E. Weibel as a demonstration of the STM, which was developed by Binnig and Rohrer at IBM's Zurich Research Laboratory.The full structure with positions of all reconstructed atoms has also been confirmed by massively parallel computation.A number of similar DAS reconstructions have also been observed on Si (111) in non-equilibrium conditions in a (2n+1)×(2n+1) pattern, and include 3×3, 5×5 and 9×9 reconstructions.