Post date: Mar 12, 2018 2:02:37 PM
The charge density accumulation within the interlayer space in layered materials has been both observed from high-level theory (DMC, Black-P, Nano Lett 15, 8170), and X-ray experiments (TiS2, Nat Mater 17, 249). By contrast, most density functional approximations, with or without dispersion corrections, with increasing accuracies in general, predict the opposite trend. Scratching my head since the Nano Lett paper, but still have no idea at all. Fundamental, Puzzling, and Interesting.