<html><body><div style="color:#000; background-color:#fff; font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:16px"><div id="yui_3_16_0_1_1441412942765_3055">Hello all,</div><div id="yui_3_16_0_1_1441412942765_2980" dir="ltr">I'm calculating the polarization of 5 cells of PbTiO3, I have set up the one unit cell correctly and got all of the properties in a good agreement as in literature. But when I tried to calculate the polarization of the 5 cells, I got this error when I run the nscf:</div><div id="yui_3_16_0_1_1441412942765_3007" dir="ltr">error: too many bands are not converged,</div><div id="yui_3_16_0_1_1441412942765_3068" dir="ltr">The way I constructed the 5 cells is by adding c/a for the z-components of the 2nd cell, 2c/a for the z-components of the 3rd cell, 3c/z for the z-components of the 4th cell, 4c/a for the z-components of the 5th cell.<br class="" id="yui_3_16_0_1_1441412942765_3155">see this:</div><div id="yui_3_16_0_1_1441412942765_3181" dir="ltr"><b>1cell :</b></div><div id="yui_3_16_0_1_1441412942765_3569" dir="ltr"><b><br></b></div><div id="yui_3_16_0_1_1441412942765_3330" dir="ltr">ATOMIC_POSITIONS <br class="" id="yui_3_16_0_1_1441412942765_3381">Pb       0.000000000   0.000000000  -0.011923470<br class="" id="yui_3_16_0_1_1441412942765_3383">Ti       0.498189800   0.498189800   0.542939650<br class="" id="yui_3_16_0_1_1441412942765_3385">O        0.498189800   0.498189800   0.085663538<br class="" id="yui_3_16_0_1_1441412942765_3387">O        0.498189800   0.000000000   0.642799807<br class="" id="yui_3_16_0_1_1441412942765_3389">O        0.000000000   0.498189800   0.642799807<br class="" id="yui_3_16_0_1_1441412942765_3391"><br class="" id="yui_3_16_0_1_1441412942765_3397">CELL_PARAMETERS (alat)<br class="" id="yui_3_16_0_1_1441412942765_3399">   0.996379599   0.000000000   0.000000000<br class="" id="yui_3_16_0_1_1441412942765_3401">   0.000000000   0.996379599   0.000000000<br class="" id="yui_3_16_0_1_1441412942765_3403">   0.000000000   0.000000000   1.082777316<br></div><div id="yui_3_16_0_1_1441412942765_3182" dir="ltr"><br></div><div id="yui_3_16_0_1_1441412942765_3122" dir="ltr"><b id="yui_3_16_0_1_1441412942765_3622">5cells:</b></div><div id="yui_3_16_0_1_1441412942765_3328" dir="ltr"><br></div><div id="yui_3_16_0_1_1441412942765_3096" dir="ltr">ATOMIC_POSITIONS  <br class="" id="yui_3_16_0_1_1441412942765_3245">Pb      0.0000000       0.0000000      -0.01192347<br class="" id="yui_3_16_0_1_1441412942765_3247">Ti      0.4981898       0.4981898       0.54293965<br class="" id="yui_3_16_0_1_1441412942765_3249">O       0.4981898       0.4981898       0.085663538<br class="" id="yui_3_16_0_1_1441412942765_3251">O       0.4981898       0.0000000       0.642799807<br class="" id="yui_3_16_0_1_1441412942765_3253">O       0.0000000       0.4981898       0.642799807<br class="" id="yui_3_16_0_1_1441412942765_3255">Pb      0.0000000       0.0000000       1.06807653<br class="" id="yui_3_16_0_1_1441412942765_3257">Ti      0.4981898       0.4981898       1.62293965<br class="" id="yui_3_16_0_1_1441412942765_3259">O       0.4981898       0.4981898       1.165663538<br class="" id="yui_3_16_0_1_1441412942765_3261">O       0.4981898       0.0000000       1.722799807<br class="" id="yui_3_16_0_1_1441412942765_3263">O       0.0000000       0.4981898       1.722799807<br class="" id="yui_3_16_0_1_1441412942765_3265">Pb      0.0000000       0.0000000       2.14807653<br class="" id="yui_3_16_0_1_1441412942765_3267">Ti      0.4981898       0.4981898       2.70293965<br class="" id="yui_3_16_0_1_1441412942765_3269">O       0.4981898       0.4981898       2.245663538<br class="" id="yui_3_16_0_1_1441412942765_3271">O       0.4981898       0.0000000       2.802799807<br class="" id="yui_3_16_0_1_1441412942765_3273">O       0.0000000       0.4981898       2.802799807<br class="" id="yui_3_16_0_1_1441412942765_3275">Pb      0.0000000       0.0000000       3.22807653<br class="" id="yui_3_16_0_1_1441412942765_3277">Ti      0.4981898       0.4981898       3.78293965<br class="" id="yui_3_16_0_1_1441412942765_3279">O       0.4981898       0.4981898       3.325663538<br class="" id="yui_3_16_0_1_1441412942765_3281">O       0.4981898       0.0000000       3.882799807<br class="" id="yui_3_16_0_1_1441412942765_3283">O       0.0000000       0.4981898       3.882799807<br class="" id="yui_3_16_0_1_1441412942765_3285">Pb      0.0000000       0.0000000       4.30807653<br class="" id="yui_3_16_0_1_1441412942765_3287">Ti      0.4981898       0.4981898       4.86293965<br class="" id="yui_3_16_0_1_1441412942765_3289">O       0.4981898       0.4981898       4.405663538<br class="" id="yui_3_16_0_1_1441412942765_3291">O       0.4981898       0.0000000       4.962799807<br class="" id="yui_3_16_0_1_1441412942765_3293">O       0.0000000       0.4981898       4.962799807<br class="" id="yui_3_16_0_1_1441412942765_3309">CELL_PARAMETERS (alat)<br class="" id="yui_3_16_0_1_1441412942765_3311">   0.996379599   0.000000000   0.000000000<br class="" id="yui_3_16_0_1_1441412942765_3313">   0.000000000   0.996379599   0.000000000<br class="" id="yui_3_16_0_1_1441412942765_3315">   0.000000000   0.000000000   5.413886650<br></div><div id="yui_3_16_0_1_1441412942765_3070" dir="ltr"><br></div><div id="yui_3_16_0_1_1441412942765_2979">Is there any problems with the construction of the supercell?</div><div id="yui_3_16_0_1_1441412942765_3571"><br></div></div></body></html>