<div dir="ltr"><span style="font-size:12.8px">Dear QE users,</span><div style="font-size:12.8px"><br></div><div style="font-size:12.8px">I'm trying to reproduce the Li adsorbed graphene with DFT-D2 using QE. The adsorption energy is very much underestimated (-0.66 eV/Li) as compared to the values found in the literature. My SIESTA vdW-DF/DZP value is -1.11 eV/Li, pretty much in agreement with the literature. I have used different cutoff values with different pseudopotentials. I don't know where is the problem. Following is one of my inputs. Need your suggestions, please. Thanks</div><div style="font-size:12.8px"><br></div><div style="font-size:12.8px"><div>&CONTROL</div><div>  calculation='vc-relax',</div><div> outdir='.',</div><div> prefix='calc',</div><div> pseudo_dir='.',</div><div> verbosity='high',</div><div> tstress=.true.</div><div>tprnfor=.true.</div><div>etot_conv_thr=1.0D-4</div><div>forc_conv_thr=1.D-3</div><div>wf_collect=.true.</div><div>nstep=1000</div><div>/</div><div><br></div><div>&SYSTEM</div><div> ibrav=0,</div><div> nat=51,</div><div> ntyp=2,</div><div> ecutwfc=40,</div><div> ecutrho=320,</div><div>  input_dft='PBE',</div><div> occupations='smearing',</div><div> smearing='mp',</div><div> degauss=0.01d0,</div><div> vdw_corr='Grimme-D2',</div><div>! nspin=2,</div><div>! starting_magnetization(1)=0.7</div><div>! starting_magnetization(2)=0.6</div><div>/</div><div><br></div><div>&ELECTRONS</div><div>  diagonalization='cg',</div><div> conv_thr=1d-08,</div><div> mixing_mode='local-TF',</div><div> mixing_beta=0.500d0,</div><div> electron_maxstep=2000</div><div>/</div><div>&IONS</div><div>ion_dynamics='bfgs'</div><div>/</div><div>&CELL</div><div>  cell_dynamics = 'bfgs' ,</div><div> cell_dofree='2Dxy'</div><div>/</div><div>ATOMIC_SPECIES</div><div>C 12.010700d0 C.pbe-van_ak.UPF</div><div>Li 6.941000d0 Li.pbe-n-van.UPF </div><div>CELL_PARAMETERS (angstrom)</div><div> 12.353060724  0.000889035 -0.201450000</div><div> -6.175669462 10.698563666  0.201310000</div><div> -0.000049454  0.000028549 20.000000000</div><div><br></div><div>ATOMIC_POSITIONS (angstrom)</div><div>C    -0.123777599  0.044352021  0.750813339</div><div>C    2.347139643  0.044536664  0.710530839</div><div>C    4.816959818  0.046608474  0.671588196</div><div>C    7.288030852  0.047974520  0.631371477</div><div>C    9.759254756  0.046949526  0.590970165</div><div>C    -1.361324273  2.182837743  0.784592128</div><div>C    1.111661447  2.176898866  0.738849472</div><div>C    3.584693057  2.183131578  0.703985603</div><div>C    6.053702309  2.186196980  0.671658550</div><div>C    8.522771292  2.186413475  0.631364175</div><div>C    -2.598243992  4.325485482  0.824910219</div><div>C    -0.131078480  4.322022349  0.764237921</div><div>C    2.354133011  4.322141066  0.723759919</div><div>C    4.821870209  4.325914119  0.703967494</div><div>C    7.288439627  4.327051393  0.671562970</div><div>C    -3.831089225  6.466525503  0.871657296</div><div>C    -1.366959478  6.470638409  0.819586551</div><div>C    1.111648295  6.474564682  0.764205441</div><div>C    3.590771165  6.470877940  0.738791095</div><div>C    6.055337825  6.467163164  0.710460311</div><div>C    -5.064123742  8.605360424  0.914570582</div><div>C    -2.595447017  8.606844025  0.871611006</div><div>C    -0.124940436  8.609595937  0.824824937</div><div>C    2.349153535  8.609719150  0.784488796</div><div>C    4.820054590  8.607291549  0.750697179</div><div>C    -0.125510159  1.469181337  0.757732918</div><div>C    2.348583973  1.469399905  0.717413261</div><div>C    4.819499832  1.472058312  0.683659878</div><div>C    7.288388407  1.473415839  0.646082581</div><div>C    9.757057163  1.472349661  0.603098319</div><div>C    -1.367183927  3.608059861  0.792700719</div><div>C    1.111411672  3.604765482  0.737260404</div><div>C    3.590550668  3.608523771  0.711920217</div><div>C    6.055141240  3.612373570  0.683651546</div><div>C    8.521773207  3.612481509  0.643390074</div><div>C    -2.598108408  5.752895502  0.838312859</div><div>C    -0.130966528  5.757101185  0.777712574</div><div>C    2.354245670  5.757343547  0.737229826</div><div>C    4.822007602  5.753541812  0.717366687</div><div>C    7.288591341  5.752608946  0.684948021</div><div>C    -3.829804361  7.892507839  0.886438561</div><div>C    -1.360854441  7.895696352  0.838263118</div><div>C    1.112121068  7.902104754  0.792620096</div><div>C    3.585162055  7.896134775  0.757637017</div><div>C    6.054187493  7.893269674  0.725270353</div><div>C    1.111459010 -0.667769729  0.725378109</div><div>C    3.582681447 -0.666400412  0.685002360</div><div>C    6.052708940 -0.664305301  0.643406933</div><div>C    8.523624623 -0.664119335  0.603107212</div><div>C    10.993446884 -0.665855193  0.564139854</div><div>Li    1.142006551  5.022080560  2.622103194</div><div>K_POINTS automatic</div><div> 6 6 1 0 0 0</div></div></div>