Effects of in-plane stiffness and charge transfer on thermal expansion of monolayer transition metal dichalcogenide |
(a) Top and (b) side views of the atomic structure of monolayer MX 2. The figure shows a 4×4 supercell, and the primitive unit cell with lattice vectors a and b (| a | = | b |) is highlighted by a parallelogram. The relevant internal structural parameters are also indicated. (c) Corresponding Brillouin zone with some high-symmetry points. |