hi,<br> I performed other USPPs tests (blyp-van_ak, pw91-van_ak, pz-van_ak) and found that all these calculations with USPPs were not convergence both in press and Etot.For example, with blyp-van_ak( result is at the bottom of the mail).All these USPPs are downloaded from the homepage of PWSCF/pseudopotential.
<br> However, this unconvergence situation disappeared with NCPP (PBE-TM-GGA, converted from fhi format PP using fhi2upf code). The result is at the bottom as well.<br> As Axel Kohlmeyer mentioned:<br> "please try a different Li pseudopotential (
i.e. a non-ak one).<br>the one you are using seems to have some not yet understood<br>problems for higher-order properties: lattice constant from<br>EOS fit, MD and geometry optimizations were fine, phonons<br>were bad."
<br> And can anyone tell me what does the 'ak'(in blyp-van_ak) mean? What kind of systems are these 'ak' USPPs suitable for calculation? <br><br>WITH blyp-van_ak USPP:------------------------------------------------------
<br> ---! convergence scf caculation for Li2O !---<br> ecutwfc = 100 Ry, ecutrho = 320 Ry :<br>! total energy = -61.82021122 Ry<br> total stress (Ry/bohr**3) (kbar) P=
19.03<br> ecutwfc = 100 Ry, ecutrho = 360 Ry :<br>! total energy = -61.82317722 Ry<br> total stress (Ry/bohr**3) (kbar) P= -6.75<br> ecutwfc = 100 Ry, ecutrho = 400 Ry :
<br>! total energy = -61.82694596 Ry<br> total stress (Ry/bohr**3) (kbar) P= 4.67<br> ecutwfc = 100 Ry, ecutrho = 600 Ry :<br>! total energy = -61.82089409
Ry<br> total stress (Ry/bohr**3) (kbar) P= 4.29<br> ecutwfc = 100 Ry, ecutrho = 800 Ry :<br>! total energy = -61.81983678 Ry<br> total stress (Ry/bohr**3) (kbar) P=
19.40<br> ecutwfc = 100 Ry, ecutrho = 1000 Ry :<br>! total energy = -61.82031614 Ry<br> total stress (Ry/bohr**3) (kbar) P= 22.33<br> ecutwfc = 200 Ry, ecutrho = 800 Ry :
<br>! total energy = -61.82432402 Ry<br> total stress (Ry/bohr**3) (kbar) P= 9.13<br> ecutwfc = 200 Ry, ecutrho = 1000 Ry :<br>! total energy = -61.82480674
Ry<br> total stress (Ry/bohr**3) (kbar) P= 12.09<br> ecutwfc = 200 Ry, ecutrho = 1600 Ry :<br>! total energy = -61.82437317 Ry<br> total stress (Ry/bohr**3) (kbar) P=
6.83<br> ecutwfc = 200 Ry, ecutrho = 1800 Ry :<br>! total energy = -61.82423710 Ry<br> total stress (Ry/bohr**3) (kbar) P= 5.72<br>-------------------------------------------------------------------------------
<br> <br>WITH PBE-MT-GGA NCPP:-----------------------------------------------------------<br> ---! convergence scf caculation for Li2O !---<br> ecutwfc = ecut = 50 Ry :<br>! total energy = -33.53719310
Ry<br> total stress (Ry/bohr**3) (kbar) P= -329.31<br> ecutwfc = ecut = 80 Ry :<br>! total energy = -33.60362083 Ry<br> total stress (Ry/bohr**3) (kbar) P= -
46.81<br> ecutwfc = ecut = 100 Ry :<br>! total energy = -33.60420031 Ry<br> total stress (Ry/bohr**3) (kbar) P= -48.44<br> ecutwfc = ecut = 140 Ry :<br>! total energy = -
33.60518304 Ry<br> total stress (Ry/bohr**3) (kbar) P= -46.36<br> ecutwfc = ecut = 180 Ry :<br>! total energy = -33.60525632 Ry<br> total stress (Ry/bohr**3) (kbar) P= -
45.97<br> ecutwfc = ecut = 200 Ry :<br>! total energy = -33.60552604 Ry<br> total stress (Ry/bohr**3) (kbar) P= -46.30<br> ecutwfc = ecut = 240 Ry :<br>! total energy = -
33.60553853 Ry<br> total stress (Ry/bohr**3) (kbar) P= -46.24<br> ecutwfc = ecut = 280 Ry :<br>! total energy = -33.60553917 Ry<br> total stress (Ry/bohr**3) (kbar) P= -
46.23<br> ecutwfc = ecut = 300 Ry :<br>! total energy = -33.60553970 Ry<br> total stress (Ry/bohr**3) (kbar) P= -46.24<br> ecutwfc = ecut = 340 Ry :<br>! total energy = -
33.60553987 Ry<br> total stress (Ry/bohr**3) (kbar) P= -46.23<br> ecutwfc = ecut = 400 Ry :<br>! total energy = -33.60554013 Ry<br> total stress (Ry/bohr**3) (kbar) P= -
46.23<br>---------------------------------------------------------------------------------