Dear all<br>I did convergence tests for chromium. The ecut value i obtained for energy converged to 1mRyd is 60Ryd! which i believe is very high for an Ultra Soft PP can somebody tell me if i am doing something wrong. Given below are my sample input file and ecut vs total energy.<br>
<br>&control<br>calculation = 'scf',<br>restart_mode='from_scratch',<br>outdir='/home/sai/softwares/espresso-4.0.1/workspace/temp',<br>prefix='chromium'<br>pseudo_dir='/home/sai/softwares/espresso-4.0.1/pseudo/',<br>
/<br>&system<br>ibrav=3<br>celldm(1)=5.450000,<br>nat=1,<br>ntyp=1<br>ecutwfc=15,<br>ecutrho=150,<br>occupations='smearing',<br>smearing='mp',<br>degauss=0.005000<br>/<br>&electrons<br>conv_thr=1.D-8,<br>
diagonalization='david',<br>mixing_mode='plain',<br>mixing_beta= 0.3<br>electron_maxstep=1000<br>/<br>ATOMIC_SPECIES<br>Cr 51.9961 Cr.pbe-sp-van.UPF<br>ATOMIC_POSITIONS (crystal)<br>Cr 0.00000000 0.00000000 0.00000000<br>
K_POINTS {automatic}<br>12 12 12 0 0 0<br><br>ecut energy<br>15 -171.52805273<br>20 -173.85044031<br>25 -174.14015464<br>30 -174.15592557<br>35 -174.16252481<br>40 -174.17616814<br>45 -174.18792735<br>
50 -174.19506225<br>55 -174.19773267<br>60 -174.19824847<br clear="all"><br>-- <br>U.Saibabu<br>PhD student,<br>Deformation mechanisms modeling group,<br>Materials engineering department,<br>IISc Bangalore,<br>India.<br>
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