<div>Dear CP2K users,</div><div><br></div><div>I am trying to monitor the stress tensor in my ab initio MD simulation in NPT ensemble using CP2K version 7.1. I wrote two print sections, one in FORCE_EVAL section (to print stress file) as<br></div><div>...<br></div><div><span style="color: green;"><font size="2">  &PRINT<br>    &FORCES             ON<br>      FILENAME          =forces<br>    &END FORCES<br>    &STRESS_TENSOR      ON<br>        FILENAME        =stress<br>    &END STRESS_TENSOR<br>  &END PRINT<br>  STRESS_TENSOR         ANALYTICAL</font></span></div><div><font size="2"><br></font></div><div><font size="2">and another in PRINT of MOTION section (to get pressure file)<br></font></div><div><font size="2">...<br></font></div><div><span style="color: green;"><font size="2">        &STRESS<br>            &EACH<br>                MD 1<br>            &END<br>            FILENAME pressure<br>        &END STRESS</font></span></div><div><br></div><div></div><div>After running the job , I got following output in the stress file:</div><div><font size="3"> <span style="color: green;"><font size="2">STRESS TENSOR [GPa]</font></span></font><br><font size="2"><span style="color: green;">            X               Y               Z<br>  X       0.00106044     -0.00003023     -0.00393423<br>  Y      -0.00003023      0.01251158      0.00014630<br>  Z      -0.00393423      0.00014630      0.00717328<br>  1/3 Trace(stress tensor):   6.91510096E-03<br>  Det(stress tensor)      :  -9.84767286E-08<br> EIGENVECTORS AND EIGENVALUES OF THE STRESS TENSOR<br>         -0.00086519      0.00909269      0.01251781<br><br>          0.89817098     -0.43935160     -0.01609565<br>         -0.00277868     -0.04228259      0.99910183<br>          0.43963755      0.89731954      0.03919782<br>  ==============================================================================<br>   Stress Tensor Components (GPW/GAPW)<br>                                                1/3 Trace           Determinant<br>   Kinetic Energy Stress                       1.22833622            0.02852337<br>   Basis Overlap Stress                        0.30458944            0.01186246<br>   ES + XC Stress                          -1736.32537740      ****************<br>   vdW correction (ff) Stress                 -0.00517761           -0.00000010<br>   Local Pseudopotential/Core Stress          -0.88167272           -0.56052030<br>   Nonlocal Pseudopotential Stress             2.92262879           20.96427765<br>   Exact Exchange Stress                      -0.00000000           -0.00000000<br>   Sum of Parts Stress                     -1732.75667328      ****************<br>   Total Stress                                0.00785295           -0.00000014<br>  ==============================================================================<br> STRESS TENSOR [GPa]<br>            X               Y               Z<br>  X      -0.05130320      0.02112443     -0.15716038<br>  Y       0.02112443      0.07439468     -0.03381687<br>  Z      -0.15716038     -0.03381687      0.04697689<br>  1/3 Trace(stress tensor):   2.33561233E-02<br>  Det(stress tensor)      :  -1.75455374E-03</span></font></div><div></div><div><br></div><div>while in pressure file I got following output</div><div><font size="2"><span style="color: green;"> <br></span></font></div><div><font size="2"><span style="color: green;">#   Step   Time [fs]            xx [bar]            xy [bar]            xz [bar]            yx [bar]            yy [bar]            yz [bar]            zx [bar]            zy [bar]            zz [bar]<br>       0       0.000     2291.7724124002       -7.8261381151      -11.6256055821       -7.8261381151     2225.2853884787      190.2135354318      -11.6256055821      190.2135354318     2617.3106021379<br>       1       0.500     1721.2682620818      206.1262199908    -1539.1469767016      206.1262199908     2804.1547381410     -143.2394364947    -1539.1469767016     -143.2394364947     2958.6420055205</span></font><br></div><div><br></div><div>Both files have values different units (GPa in stress file and bar in pressure file). After converting values to same unit (say bar) the xx stress value <span><span>10.60 bar (<span><span>0.00106044 GPa</span></span>) does not match with the value of  2291.77</span></span> bar in the pressure file. Can you please help me to understand this ? Am I doing something wrong in my input file. The print output of cell vectors from the MOTION section is following:</div><div><br></div><div><span style="color: green;"><font size="2">#   Step   Time [fs]       Ax [Angstrom]       Ay [Angstrom]       Az [Angstrom]       Bx [Angstrom]       By [Angstrom]       Bz [Angstrom]       Cx [Angstrom]       Cy [Angstrom]       Cz [Angstrom]      Volume [Angstrom^3]<br>       0       0.000       16.9813194275        0.0000000000        0.0000000000        0.0009342941       17.1132431030        0.0000000000       -0.0392083935        0.0056124185       17.0369434357          4951.0285723949<br>       1       0.500       16.9878393880       -0.0026240361        0.0088682212       -0.0017097687       17.1090517191        0.0016270059       -0.0303270449        0.0072363688       17.0367331490          4951.6596469487</font></span></div><div><font size="2"><br></font></div><div><font size="2">Many thanks ,<br></font></div><div></div><div><font size="2">Abhishek</font><br></div><div><br></div><div><br></div><div><br></div>

<p></p>

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