We considered two different GO models with identical chemical composition but differences in the spatial arrangement of the functional groups. Starting point is an orthorhombic periodic supercell of graphene consisting of 72 carbon atoms. In each model, 12 hydroxyl and 6 epoxide groups were grafted on the basal plane of graphene. This means that there are 24, out of 72, sp 3 C atoms that are bonded to oxygen functional groups resulting in a functionalization rate of 25%, a typical value for GO. The OH groups have been systematically placed in a way that two adjacent C atoms bear a pair of OH groups coming out of the opposite sides of the graphene sheet (cf. Figure ). It is noteworthy that all the above-mentioned features of our models align with the GO models of Mouhat et al. Two configurations have been considered in our study as shown in Figure . In the first GO model, OGO, there is a fully oxidized domain surrounded by a graphene-like region.