Dear all<br><br>I perform the relax calculate to the crystal structure. After 11 step bfgs,  the total force and total scf correction had reach to the criterion, however, the total stress was so big P=-3443.87. I have no idea about deal with the case,  could anyone give some advices? Thanks in advance.<br>

<br>the input file<br>: &CONTROL<br>                 calculation = 'scf' ,<br>                restart_mode = 'from_scratch' ,<br>                  wf_collect = .true. ,<br>                      outdir = '/lustre/AIOFM/gxgu/workLCAF/5/temp/' ,<br>

                      wfcdir = '/lustre/AIOFM/gxgu/workLCAF/5/wftemp/' ,<br>                  pseudo_dir = '/home/AIOFM/gxgu/work/NCPP/' ,<br>                      prefix = 'LCAF' ,<br>               etot_conv_thr = 1.0D-7 ,<br>

               forc_conv_thr = 1.0D-6 ,<br>                       nstep = 100 ,<br>                     tstress = .true. ,<br>                     tprnfor = .true. ,<br>                    dipfield = .true. ,<br> /<br> &SYSTEM<br>

                       ibrav = 4,<br>                   celldm(1) = 9.42432151,<br>                   celldm(3) = 1.94804220,<br>                         nat = 18,<br>                        ntyp = 4,<br>                     ecutwfc = 30 ,<br>

                     ecutrho = 120 ,<br>                       nosym = .false. ,<br> /<br> &ELECTRONS<br>            electron_maxstep = 100,<br>                    conv_thr = 1.0D-10 ,<br> /<br>ATOMIC_SPECIES<br>   Li    6.94100  03-Li.LDA.fhi.UPF <br>

   Al   26.98154  13-Al.LDA.fhi.UPF <br>   Ca   40.07800  20-Ca.LDA.fhi.UPF <br>    F   18.99840  09-F.LDA.fhi.UPF <br>ATOMIC_POSITIONS crystal <br>   Li      0.333333333    0.666666667    0.250000000    <br>   Li     -0.333333333   -0.666666667   -0.250000000    <br>

    F      0.389997       0.045970       0.148326    <br>    F     -0.045970       0.344027       0.148326    <br>    F     -0.344027      -0.389997       0.148326    <br>    F     -0.045970      -0.389997       0.351674    <br>

    F     -0.344027       0.045970       0.351674    <br>    F      0.389997       0.344027       0.351674    <br>    F     -0.389997      -0.045970      -0.148326    <br>    F      0.045970      -0.344027      -0.148326    <br>

    F      0.344027       0.389997      -0.148326    <br>    F      0.045970       0.389997       0.648326    <br>    F      0.344027      -0.045970       0.648326    <br>    F     -0.389997      -0.344027       0.648326    <br>

   Al      0.666666667    0.333333333    0.250000000    <br>   Al     -0.666666667   -0.333333333   -0.250000000    <br>   Ca      0.000000000    0.000000000    0.000000000    <br>   Ca      0.000000000    0.000000000    0.500000000    <br>

K_POINTS automatic <br>  16 16 16   0 0 0 <br><br>best regart<br><br>Wang Di<br clear="all"><br>-- <br>-----------------------------------------------------------------<br><i style="font-family: comic sans ms,sans-serif;">Wang Di</i><i style="font-family: comic sans ms,sans-serif;"><br>

The Crystal Lab,</i><br><i style="font-family: comic sans ms,sans-serif;"><span style="font-size: 10pt;" lang="EN-US">AnHui Institute of Optics and Fine Mechanics, </span></i><i style="font-family: comic sans ms,sans-serif;"></i><br>

<i style="font-family: comic sans ms,sans-serif;"><span style="font-size: 10pt;" lang="EN-US">Chinese Academy of Sciences,</span></i><i style="font-family: comic sans ms,sans-serif;"><span style="font-size: 10pt;" lang="EN-US"><br>

No350. , Shushanhu Road, Hefei,
230031, China</span><span style="font-size: 10pt;" lang="EN-US"></span></i><i style="font-family: comic sans ms,sans-serif;"><span style="font-size: 10pt;" lang="EN-US">,<br>E-mail: didi5158 @gmail.ocm</span></i><i style="font-family: comic sans ms,sans-serif;">

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