In contrast to previous results of simulations of the ground-state structures of high-angle twist grain boundaries in Si at absolute zero, in which amorphous intergranular films were found, recent experimental results impliedstructural order in some high-angle twist boundaries. With a novel protocol for simulating twist GB’s, which allows the number of atoms at the boundary to vary, new lower-energy ordered structures were found. Structural units, common to many of these boundaries were also found; which was further evidence that these boundary structures were not arbitrary or disordered. A detailed exposition of the results for 5 boundaries was given and it was concluded that structural order was present in all of them.

Order and Structural Units in Simulations of Twist Grain Boundaries in Silicon at Absolute Zero. S.von Alfthan, K.Kaski, A.P.Sutton: Physical Review B, 2006, 74[13], 134101 (14pp)