Deformation mechanisms from 0 to 25% strain, presented schematically. (a) The motion of particles on the through plane: the inter-sphere distance in the stretching direction increases gradually during uniaxial stretching, while that in the b axis does not change. (b) A through view of the lattice vectors, a1, a2 and a3, at 0% strain (left-hand side) and at arbitrary strain (right-hand side). The local strains, ∊1, ∊2 and ∊3, are indicated. Gray and white balls represent the center positions of a particle in the lower layer (A layer) and in the upper layer (B layer), respectively. (c) An edge view of the lattice vectors.