For the prediction of the band gap, we took into consideration that 33 out of the 53 monolayers are metallic (zero band gap) and excluded them from our data set. Within the set of 267 bilayers selected above, the number of bilayers formed from these 20 non-metallic monolayers is 49. The application of DFT methods with vdW correlation correction to layered materials has been demonstrated to yield accurate results for the interlayer distances and the binding energies. We use the TS method which accurately predicts the values of interlayer distances compared with the available experimental values as accurately as the benchmark Random Phase Approximation (RPA) method. Figure : Comparison between the c lattice parameter for 11 2D materials predicted using the TS vdW correlation, and the experimental values. Figure compares the values of the c lattice parameter for the 11 2D materials predicted using the TS vdW correlation RPA, and the experimental values. The DFT method is clearly able to accurately recapitulate the experimental lattice parameters. These values are for pristine bulk materials, not hybrid materials, however. The choice of the best method for hybrid multilayered materials is still an open problem, and is currently the subject of an ongoing theoretical investigation.