SCF convergence issue with diffuse functions on basis set

vifontenelle · October 13, 2025, 7:03pm

But does this change anything on the HF energies and MBD? because on the output showed this:

+------------------------------------------+
| END Calculate Hirshfeld volumes          |
+------------------------------------------+

 continuing MBD-vdW initialization
 --------------------------------------------------

 LibMBD called for the MBD step
 Number of frequency grid points:           21
 Energy from LibMBD: -1.867469028979940E-004
 No MBD force evaluation
+------------------------------------------+
| END Calculate MBD vdW contributions      |
+------------------------------------------+
MBDVDW|MBDVDW
MBD vdW energy contribution: -1.8674690290e-04 au
Will be added to SCF energy
MBDVDW|MBDVDW
    2    -187.7190549375      4.17E-06 Convergence criterion met
 ---------------------------------------
 SCF time:  CPU 726632.02 s  wall 55796.96 s
 SCF   energy =  -187.71905494
 Total energy =  -187.71905494

and only after computing Mulliken charges it crashed with this error.

jherbert · October 13, 2025, 11:57pm

can you post a smaller example with ghost atoms that crashes? then I will investigate

vifontenelle · October 14, 2025, 11:00am

I don’t have any smaller example. I am running only for these type of system the ghost atoms. For some of the configurations (varying the CO2 position) I tested with PBE0+MBD and it converged without this error, so I don’t know if maybe is an specific system coordinate problem or maybe the problem is with the HF calculation.

jherbert · October 14, 2025, 11:23am

It’s probably fine if you got to an SCF energy, but if you want someone to track down the bug then construct some smaller system that has ghost atoms and exhibits the crash. Calculations that take hours to run make for lousy debugging jobs.

vifontenelle · October 22, 2025, 10:02am

I have one more question. I managed to solve all the convergence problem that I was having, now I am facing one more problem regarding the HF-R2SCAN calculation:

$molecule
0 1
O     17.030923   20.180604    7.674996
C     16.390923   19.250604    7.458996
O     15.750923   18.321604    7.241996
@H 8.929130 15.324930 3.187710
@H 8.930730 15.331990 10.130110
@O 17.959280 14.394630 15.997290
@H 21.131970 9.313330 1.398210
@C 20.000300 11.332980 15.970020
@H 21.459350 7.601420 12.446460
@Mg 16.619130 14.509750 3.653030
@Mg 16.618420 14.511030 10.595030
@C 20.088090 10.283970 -2.621040
@H 21.461050 7.598710 -1.437680
@Mg 18.325420 14.668470 5.967170
@Mg 18.324720 14.669750 12.909170
@H 10.614310 14.362670 -0.895210
@H 18.960930 11.288590 -1.072700
@C 20.482050 9.215110 19.150700
@H 10.582310 14.756880 12.965960
@H 21.459430 7.599840 5.504170
@O 17.757260 15.887300 -2.515010
@C 20.002410 11.329130 -4.855980
@H 10.580620 14.753470 6.025000
@Mg 17.335540 16.066380 1.338820
@Mg 17.334840 16.067660 8.280820
@H 20.931130 21.840000 5.336660
@C 19.388210 19.185700 -2.543490
@C 20.492560 10.285190 -4.027420
@C 19.245310 11.312980 18.715550
@O 17.756550 15.888580 4.426990
@O 17.755850 15.889860 11.368990
@O 9.578690 15.153940 2.487820
@O 9.577990 15.155220 9.429810
@C 18.920740 17.945250 -2.032450
@H 20.450280 8.404490 20.840910
@H 20.279180 11.363710 -5.897830
@Mg 18.326130 14.667190 -0.974830
@H 21.853870 22.311420 7.843540
@H 21.871160 22.308660 14.776590
@O 16.562620 14.964390 6.741040
@O 16.561910 14.965660 13.683040
@O 21.287740 8.248760 4.804280
@O 21.287030 8.250050 11.746280
@O 21.414010 21.841250 0.173780
@O 21.413310 21.842530 7.115780
@C 18.755160 12.356920 17.886980
@O 10.999570 15.740930 18.106100
@H 18.971680 11.269820 19.757300
@C 18.765680 13.427000 -5.291130
@O 17.960690 14.392070 2.113290
@O 17.959980 14.393350 9.055290
@H 19.228620 19.427410 -3.579580
@C 20.490450 10.289030 16.798580
@O 17.962110 17.412180 2.692480
@O 17.961400 17.413460 9.634480
@O 11.000970 15.738360 4.222100
@O 11.000270 15.739640 11.164100
@O 21.288440 8.247480 -2.137720
@C 10.813940 15.371230 16.834580
@O 17.926630 13.308600 -2.376490
@O 19.178630 13.450630 -6.562670
@O 15.641330 15.537330 16.134870
@O 15.140340 14.379960 5.006750
@O 15.139640 14.381240 11.948750
@O 20.070500 9.188920 6.538230
@O 20.069800 9.190200 13.480230
@O 21.208440 20.317640 1.908290
@O 21.207730 20.318920 8.850290
@C 19.247420 11.309130 -2.110450
@O 17.962810 17.410900 -4.249520
@H 18.797350 14.228450 -6.996000
@O 20.069090 9.191480 20.422230
@O 19.177920 13.451910 0.379330
@O 19.177220 13.453190 7.321330
@O 20.458690 21.330640 4.663750
@O 20.457980 21.331930 11.605760
@H 17.815730 13.113650 19.386820
@H 20.258390 11.364410 14.924610
@O 15.642740 15.534770 2.250870
@O 15.642030 15.536050 9.192870
@O 21.321100 9.333520 16.236050
@O 21.323210 9.329670 -4.589950
@C 18.189770 17.065550 -2.977860
@O 9.577280 15.156500 16.371820
@O 10.499280 14.582270 0.035990
@O 10.498580 14.583560 6.977990
@O 21.207020 20.320200 15.792300
@C 13.249260 15.393270 16.400190
@O 17.925920 13.309880 4.565510
@O 17.925220 13.311160 11.507510
@H 15.539480 15.703000 17.078460
@O 18.711160 16.400460 6.879020
@O 18.710460 16.401740 13.821020
@C 11.941250 15.177710 15.889230
@O 20.459400 21.329360 -2.278250
@O 21.322500 9.330950 2.352050
@O 21.321800 9.332240 9.294050
@H 13.329290 15.654290 17.442990
@O 17.924510 13.312440 18.449510
@C 18.189070 17.066830 3.964140
@C 18.188360 17.068110 10.906140
@C 10.815350 15.368670 2.950580
@C 10.814650 15.369950 9.892580
@C 19.159630 12.358140 16.480610
@H 20.935560 21.837750 12.276650
@C 19.161740 12.354300 -4.345390
@O 17.961390 14.390780 -4.828710
@C 15.325960 14.749660 6.278270
@C 15.325260 14.750940 13.220270
@C 20.483450 9.212550 5.266700
@C 20.482750 9.213830 12.208700
@C 20.981490 20.662990 0.636640
@C 20.980780 20.664280 7.578640
@H 21.132120 9.317410 8.340280
@C 20.085980 10.287810 18.204960
@O 21.286330 8.251320 18.688280
@C 18.764970 13.428280 1.650870
@C 18.764270 13.429560 8.592870
@C 18.920030 17.946530 4.909550
@C 18.919320 17.947810 11.851550
@C 11.942660 15.175150 2.005230
@C 11.941960 15.176430 8.947230
@C 14.199360 14.941910 0.281630
@C 14.198650 14.943190 7.223620
@C 20.087390 10.285250 4.320960
@C 20.086690 10.286530 11.262960
@C 20.249820 19.784580 6.633230
@C 20.249110 19.785870 13.575230
@C 19.161030 12.355580 2.596610
@C 19.160330 12.356860 9.538610
@C 20.046520 20.133730 5.226720
@C 20.045820 20.135010 12.168730
@C 14.400080 15.293060 1.688000
@C 14.399370 15.294340 8.630000
@C 11.741940 14.823990 0.598860
@C 11.741240 14.825270 7.540860
@C 18.756560 12.354360 4.002980
@C 18.755860 12.355640 10.944980
@C 19.123330 17.597380 6.316050
@C 19.122620 17.598660 13.258060
@C 20.491860 10.286470 2.914580
@C 20.491160 10.287750 9.856580
@C 19.387510 19.186980 4.398510
@C 19.386800 19.188260 11.340510
@C 13.250660 15.390710 2.516190
@C 13.249960 15.391990 9.458180
@C 12.890650 14.727620 6.712670
@C 12.889940 14.728900 13.654670
@C 19.246720 11.310420 4.831550
@C 19.246020 11.311700 11.773550
@C 19.783050 18.542850 0.202270
@C 19.782340 18.544130 7.144270
@C 20.001700 11.330420 2.086020
@C 20.001000 11.331700 9.028020
@H 19.242440 19.424830 3.358860
@H 19.241170 19.427710 10.301180
@H 13.377740 15.649240 3.556130
@H 13.383180 15.651530 10.497170
@H 12.783270 14.484460 5.668150
@H 12.790830 14.490070 12.608540
@H 18.957640 11.291780 5.871010
@H 18.955340 11.290940 12.811430
@H 19.942290 18.309580 1.244210
@H 19.937180 18.308850 8.186510
@H 20.261130 11.353650 1.039810
@H 20.262380 11.358650 7.982490
@O 21.412590 21.843820 14.057800
@H 21.442370 9.538990 -5.522740
@O 19.176510 13.454480 14.263330
@H 21.134280 9.313610 15.280170
@C 18.757270 12.353080 -2.939020
@H 8.939870 15.325670 17.082610
@O 10.497870 14.584840 13.919990
@O 20.071200 9.187630 -0.403770
@O 16.563320 14.963100 -0.200960
@O 18.711870 16.399180 -0.062980
@C 14.197950 14.944470 14.165620
@C 20.250530 19.783300 -0.308780
@C 12.891360 14.726340 -0.229330
@C 15.326670 14.748370 -0.663730
@C 19.781640 18.545410 14.086270
@C 20.980070 20.665560 14.520650
@C 11.740530 14.826560 14.482860
@C 19.124030 17.596090 -0.625950
@C 18.763560 13.430840 15.534870
@C 20.484160 9.211270 -1.675300
@C 14.398670 15.295620 15.572000
@C 20.047230 20.132440 -1.715280
@H 12.789980 14.468370 -1.271140
@O 15.141050 14.378680 -1.935250
@H 19.953600 18.316360 15.124070
@H 21.858680 22.312100 0.897900
@H 20.894760 21.862090 -1.597760
@H 17.715230 15.015010 15.270820
@H 16.034640 14.244070 -2.345400
@H 17.617140 16.598930 -4.678420
$end

$rem
JOBTYPE sp
METHOD R2SCAN
DC_DFT TRUE
MEM_TOTAL 430000
SCF_GUESS READ
XC_GRID  2
BASIS Def2-TZVPD
thresh 14
s2thresh 16
MEM_STATIC 8000
$end

The ghost atoms I think its making the calculation to heavy and its crashing on this part:

 -------------------------------------------------------
 OpenMP Integral computing Module
 Release: version 1.0, May 2013, Q-Chem Inc. Pittsburgh
 -------------------------------------------------------
 ---------------------------------------
  Cycle       Energy         DIIS Error
 ---------------------------------------
    1    -187.7189424178      4.38E-10
    2    -187.7189424179      2.04E-10 Convergence criterion met for HF energy
   Performing an additional SCF iteration to generate DFT Fock matrix
Valid Angular Grids are :
Valid Angular Grids are :
6, 18, 26, 38, 50, 74, 86, 110, 146, 170, 194, 230
266, 302, 434, 590, 770, 974, 1202, 1454, 1730
2030, 2354, 2702, 3074, 3470, 3890, 4334, 4802, 5294
Valid Angular Grids are :
6, 18, 26, 38, 50, 74, 86, 110, 146, 170, 194, 230Valid Angular Grids are :

Is there anything I could do to make the calculation “lighter”? And solve this problem?

Thanks again for all the help.

jherbert · October 22, 2025, 10:53am

I believe there may be a bug for SCAN-based functionals with ghost atoms, which is in the process of being fixed.

vifontenelle · October 22, 2025, 12:29pm

I see. So there is nothing it can be done then right?.

jherbert · October 22, 2025, 12:41pm

See if you can get it to run with a different functional, that will test my hypothesis.