Observing the cell volumes, the agreement is not as striking, but still in line or better than the plane-wave results. Nonetheless, this could cast some doubt on the cohesive energies computed. Obtaining the correct energies on the basis of non-optimal structures would be a strong indicator for error compensation. We investigated the possibility of error compensation by recomputing the DF-LCCSD(T0)/cc-pVQZ AC(2)-QM/MM co- hesive energy from a series of different geometries. We included the experimentally determined geometries, optimising with AC(1)-QM/MM the hydrogen positions only, or the internal geometries completely. The cell parameters were hereby kept fixed. The latter structures are labeled as "H-relax" and "relax". We also included the PBE AC(2)-QM/MM geometries and finally a comparison is made with the CC geometries. The results are provided in Table .