<div dir="ltr">Dear all, <br><br>I'm trying to do cell relaxation on my Mg-Boron
systems. For some of the structures, I got extremely strange results.
The total energy diverges starting from some ionic step. For example,
here are the total energy in each ionic step for one of the problematic
run: <br>
<br>! total energy = -24.47168660 Ry<br>! total energy = -35.02062718 Ry<br>! total energy = -38.37822321 Ry<br>! total energy = -40.20237747 Ry<br>
! total energy = -40.96387007 Ry<br>
! total energy = -41.20956341 Ry<br>! total energy = -41.41389316 Ry<br>! total energy = -41.46640700 Ry<br>! total energy = -41.49930067 Ry<br>! total energy = -41.51263104 Ry<br>
! total energy = -41.53987139 Ry<br>! total energy = -41.59139496 Ry<br>! total energy = -41.55162726 Ry<br>! total energy = -41.64537650 Ry<br>! total energy = -41.67440874 Ry<br>
! total energy = -41.73712135 Ry<br>! total energy = -51.60413428 Ry<br>! total energy = -688.94041793 Ry<br>! total energy = -817.40812316 Ry<br>! total energy = -914.65691139 Ry<br>
! total energy = -980.98769592 Ry<br>! total energy = -1145.13424734 Ry<br>! total energy = -1079.87331043 Ry<br>! total energy = -1148.61890203 Ry<br>! total energy = -1147.67898328 Ry<br>
! total energy = -1147.50188067 Ry<br>! total energy = -1148.72218340 Ry<br>! total energy = -1149.83861471 Ry<br>! total energy = -1690.39538237 Ry<br>! total energy = -2822.35642442 Ry<br>
! total energy = -2718.63827111 Ry<br>! total energy = -2790.48198795 Ry<br>! total energy = -2823.74590405 Ry<br>! total energy = -2878.31317290 Ry<br>! total energy = -4478.65409327 Ry<br>
! total energy = -5464.15854938 Ry<br>! total energy =-14818.93675687 Ry<br>! total energy =-17158.30103958 Ry<br>! total energy =-18287.28161766 Ry<br><br>
and the forces:<br>
<br> Total force = 39.327209 Total SCF correction = 0.000071<br> Total force = 11.517813 Total SCF correction = 0.000029<br> Total force = 8.564152 Total SCF correction = 0.000058<br>
Total force = 3.973671 Total SCF correction = 0.000035<br> Total force = 1.056249 Total SCF correction = 0.000106<br> Total force = 0.617165 Total SCF correction = 0.000092<br>
Total force = 0.326250 Total SCF correction = 0.000046<br> Total force = 0.416678 Total SCF correction = 0.000033<br> Total force = 0.227223 Total SCF correction = 0.000033<br>
Total force = 0.501912 Total SCF correction = 0.000042<br> Total force = 0.269395 Total SCF correction = 0.000104<br> Total force = 0.369080 Total SCF correction = 0.000049<br>
Total force = 0.334142 Total SCF correction = 0.000026<br> Total force = 0.148318 Total SCF correction = 0.000034<br> Total force = 0.145030 Total SCF correction = 0.000012<br>
Total force = 0.143331 Total SCF correction = 0.000064<br> Total force = 116.856723 Total SCF correction = 0.000084<br> Total force = 65.417648 Total SCF correction = 0.000066<br>
Total force = 171.381517 Total SCF correction = 0.000070<br> Total force = 155.577114 Total SCF correction = 0.000070<br> Total force = 184.877111 Total SCF correction = 0.000057<br>
Total force = 109.156982 Total SCF correction = 0.000037<br> Total force = 142.602012 Total SCF correction = 0.000080<br> Total force = 88.522593 Total SCF correction = 0.000117<br>
Total force = 127.562744 Total SCF correction = 0.000058<br> Total force = 92.956163 Total SCF correction = 0.000108<br> Total force = 88.462372 Total SCF correction = 0.000117<br>
Total force = 84.376621 Total SCF correction = 0.000056<br> Total force = 134.526750 Total SCF correction = 0.000106<br> Total force = 282.688334 Total SCF correction = 0.000132<br>
Total force = 600.035535 Total SCF correction = 0.000078<br> Total force = 224.477965 Total SCF correction = 0.000122<br> Total force = 398.869729 Total SCF correction = 0.000123<br>
Total force = 396.502768 Total SCF correction = 0.000149<br> Total force = 420.885999 Total SCF correction = 0.000136<br> Total force = 443.182054 Total SCF correction = 0.000031<br>
Total force = 3819.452849 Total SCF correction = 0.000261<br> Total force = 1265.093632 Total SCF correction = 0.000207<br> Total force = 1027.278240 Total SCF correction = 0.000338<br>
<br>For this problematic system, this behavior is very stable. No
matter I use 'cg' or 'david', change the mixing parameter from 0.9 to
0.1, I still get similar problem. <br><br>I cannot find anything
relevant in the archive. I wonder if anyone knows what's going on here
and can help me get rid of this annoying problem. <br><br>btw, the input, output files and pseudo-potentials can be found at: <a href="http://volga.eng.yale.edu/hui/MgonBS.tar.gz">http://volga.eng.yale.edu/hui/MgonBS.tar.gz</a><br>
<br><br><br><br>Thank you very much,<br>---------------------------------------------<br>Hui Tang<br>Graduate Student<br>Department of Applied Physics<br>Yale University<br>Email: <a href="mailto:hui.tang@yale.edu">hui.tang@yale.edu</a><br>
Phone: 1-203-432-7763<br><br><br></div>