Hello, I am trying to run a sp calculation for a large system with def2-tzvpd but I am struggling to convert the calculation. When I run with Def2-TZVP it converges easily with ~4,5 scf cycles but when I add the diffusion it just give me really noisy and weird results and do not converge. I already tried the BASIS2 (basis set projection) but It gives me the same problem (gonna put an input example below). Do you know what I can try to change? (I already tried without the LEVEL SHIFT, without the SCF_GUESS flag, without S2THRESH as well but nothing worked)
Input:`$molecule
0 1
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
O     17.030923   20.180604    7.674996
C     16.390923   19.250604    7.458996
O     15.750923   18.321604    7.241996
$end
$rem
JOBTYPE sp
METHOD HF
BASIS Def2-TZVPD
CHELPG TRUE
POP_MULLIKEN TRUE
MEM_TOTAL 100000
MBDVDW MBD_SP
MBDVDW_BETA 10000
MAX_SCF_CYCLES 200
SCF_CONVERGENCE 8
THRESH 14
GUI 2
BASIS2 def2-TZVP
SCF_GUESS CORE
S2THRESH 14
LEVEL_SHIFT TRUE
LSHIFT 500
MEM_STATIC 4096
$end
And the SCF cycles is looking like this:
Cycle Energy DIIS Error
1   23543.6375163963      6.40E-02
2   27046.9758839808      5.88E-02
3   10036.6916014008      5.20E-02
4   18612.4468479886      6.59E-02
5   11519.1274259245      6.45E-02
6    5100.6012273234      4.56E-02
7    2531.7699012155      3.46E-02
8   13060.9571608931      6.18E-02
9   -2386.2616358222      3.03E-02
10    3602.7734002637      4.18E-02
11     184.3086006999      3.08E-02
12    1845.7506287005      3.91E-02
13   -5540.6657684927      1.71E-02
14    8275.1396201772      4.50E-02
15    6736.8052764968      4.13E-02
16    6617.4984400721      4.07E-02
17    3612.3299893461      3.91E-02
18    7746.9681010764      4.67E-02
19   -1596.9264381589      2.68E-02
20   -2695.1503788261      3.27E-02
21   -6150.9475788403      2.09E-02
22   -2744.0773566149      2.75E-02
23   -5007.9259096748      2.06E-02
24   -8073.1359170381      9.63E-03
25    6802.3277443085      5.34E-02
26    5390.2176533551      4.96E-02
27    3816.1072316557      4.72E-02
28    4757.6331588731      4.85E-02
29   13176.5142077793      6.59E-02
30   12436.5863208156      6.30E-02
31   12423.1385126460      6.29E-02
32   12440.6486662224      6.31E-02
33   12469.1834072102      6.34E-02
34   12852.1243656530      6.39E-02
35   11941.3820602145      6.12E-02
36    8702.0762265380      5.69E-02
37   11943.1318666469      6.32E-02
38    7582.0776518703      5.22E-02
39   19023.0413736442      7.36E-02
40   35210.3669653650      8.22E-02
Thanks a lot for the attention