Atomic stacking sequence of graphene/α-SiO2(0001) interface without relaxation (a) and in structure A (b). The yellow, gray, and red spheres show Si, C, and O atoms. The numbers are the index of atoms in the simulation. The meanings of parameters in the figure are given in the text.
Ao et al. Nanoscale Research Letters 2012 7:158 doi:10.1186/1556-276X-7-158