I am a new user of Quantum-Espresso (QE) and I am trying to study the adsorption energy of lithium ions in graphite. I want to reproduce some calculations from other people (Persson), to ensure that I am using the right parameters.
In this system the Van der Waals (vdw) interactions play an important role and I want to know more about vdw in QE. In her work Persson (Nano Lett., 2012, 12 (9), pp 4624?4628) says that there are two approacches to include vdw interactions: - "DFT-D2 approach, which adds a semiempirical pairwise force field" - "vdW-DF approach, which adds a nonlocal correlation functional that approximately account for dispersion interactions" which approach use by QE? I am using espresso-4.3.2. In my calculations I use: &SYSTEM ... london = .true., london_rcut =200, london_s6 =0.75, and ATOMIC_SPECIES C 12.0107 C.pw91-van_ak.UPF Li 6.939 Li.pw91-n-van.UPF I cant reproduce Persson calculations, but I dont know where is the problem. It is OK to use this parametres with this pseudopotentials? I have tryed changing the parametres but my calculations do not improve. QE enables to change other parameters? Thanks in advance for any help. Manuel -------------- next part -------------- An HTML attachment was scrubbed... URL: http://pwscf.org/pipermail/pw_forum/attachments/20131119/0433a54d/attachment.html
