I have a problem with geometry optimization in Gaussian software with M062X method. The structure was smoothly optimized using M062X/Gen. Nevertheless, I need very accurate results so afterwards the job was submitted once more, but this time with Opt=VeryTight
and Int=UltraFine
keywords. Nevertheless, I got the error:
Optimization stopped.
-- Number of steps exceeded, NStep= 126
-- Flag reset to prevent archiving.
... and at the end:
Error termination request processed by link 9999.
Error termination via Lnk1e in /usr/local/gaussian/2016-C.01/g16/l9999.exe at Tue Aug 25 16:05:14 2020.
What can I do? The input is following and, as I told, geometry is taken directly from the previous step which was performed using the same method and basis but without Opt=VeryTight
and Int=UltraFine
keywords.
I'm stuck, don't know what to do. Any idea?
%chk=vacCFI_7_8.chk
#p M062X/Gen
opt=(Cartesian,maxcycles=200,verytight,restart) freq
int=ultrafine
geom=check guess=read
scf=xqc
vacCFI_7_8
0 1
H 0
S 3 1.00
34.0613410 0.60251978D-02
5.1235746 0.45021094D-01
1.1646626 0.20189726
S 1 1.00
0.32723041 1.0000000
S 1 1.00
0.10307241 1.0000000
P 1 1.00
0.8000000 1.0000000
P 1 1.00
0.95774129632D-01 1.0000000
****
C 0
S 6 1.00
13575.3496820 0.22245814352D-03
2035.2333680 0.17232738252D-02
463.22562359 0.89255715314D-02
131.20019598 0.35727984502D-01
42.853015891 0.11076259931
15.584185766 0.24295627626
S 2 1.00
6.2067138508 0.41440263448
2.5764896527 0.23744968655
S 1 1.00
0.57696339419 1.0000000
S 1 1.00
0.22972831358 1.0000000
S 1 1.00
0.95164440028D-01 1.0000000
S 1 1.00
0.48475401370D-01 1.0000000
P 4 1.00
34.697232244 0.53333657805D-02
7.9582622826 0.35864109092D-01
2.3780826883 0.14215873329
0.81433208183 0.34270471845
P 1 1.00
0.28887547253 .46445822433
P 1 1.00
0.10056823671 .24955789874
D 1 1.00
1.09700000 1.0000000
D 1 1.00
0.31800000 1.0000000
D 1 1.00
0.90985336424D-01 1.0000000
F 1 1.00
0.76100000 1.0000000
****
O 0
S 6 1.00
27032.3826310 0.21726302465D-03
4052.3871392 0.16838662199D-02
922.32722710 0.87395616265D-02
261.24070989 0.35239968808D-01
85.354641351 0.11153519115
31.035035245 0.25588953961
S 2 1.00
12.260860728 0.39768730901
4.9987076005 0.24627849430
S 1 1.00
1.1703108158 1.0000000
S 1 1.00
0.46474740994 1.0000000
S 1 1.00
0.18504536357 1.0000000
S 1 1.00
0.70288026270D-01 1.0000000
P 4 1.00
63.274954801 0.60685103418D-02
14.627049379 0.41912575824D-01
4.4501223456 0.16153841088
1.5275799647 0.35706951311
P 1 1.00
0.52935117943 .44794207502
P 1 1.00
0.17478421270 .24446069663
P 1 1.00
0.51112745706D-01 1.0000000
D 1 1.00
2.31400000 1.0000000
D 1 1.00
0.64500000 1.0000000
D 1 1.00
0.14696477366 1.0000000
F 1 1.00
1.42800000 1.0000000
****
Here is .xyz geometry:
O -4.44721 1.17772 -0.00003
C -3.68389 0.06486 -0.00000
O -4.16201 -1.03886 0.00003
C -2.24755 0.39366 -0.00001
C -1.34975 -0.59256 0.00001
C 0.10468 -0.46469 0.00000
C 0.87630 -1.62398 -0.00001
C 2.26287 -1.55445 -0.00001
C 2.88570 -0.32236 -0.00001
O 4.23767 -0.13929 -0.00001
C 2.12513 0.85396 0.00001
O 2.73759 2.06167 0.00002
C 0.74994 0.77741 0.00001
H -5.36979 0.88538 -0.00002
H -1.98671 1.44280 -0.00003
H -1.74093 -1.60620 0.00003
H 0.38777 -2.58968 -0.00001
H 2.86062 -2.45869 -0.00002
H 4.69415 -0.98608 -0.00002
H 3.69353 1.92694 0.00001
H 0.19248 1.70441 0.00002
maxcycles=200
, but your error message says it stopped after only 126. 3. You haveopt=restart
, but this would be to restart a failed job; you should only needgeom=check
to extract the successful geometry. Assuming those don't help to fix your issue, it would be useful to see how close the geometry came to converging (search forItem
at the last step). $\endgroup$MaxStep=N ... Sets the maximum size for an optimization step (the initial trust radius) to 0.01N Bohr or radians. The default value for N is 30
, isn't it? 3) Yes, I have been usinggeom=check
andguess=check
and it still fails. That's why I usedopt=restart
$\endgroup$Maximum Force - 0.000006 - 0.000002 - NO.....RMS - Force - 0.000002 - 0.000001 - NO....Maximum Displacement - 0.000638 - 0.000006 - NO.......RMS - Displacement - 0.000129 - 0.000004 - NO..
As you can see they are rather close to converge.. $\endgroup$Int=(Grid=199974)
? Well, that's some kind of result the functional doesn't work though it should. M06 are widely used when describing compounds I am studying. Isn't 500 cycles too much, wouldn't it pinpoint the geometry is definitely wrong? How exactly new guess influences results? No, it has not. $\endgroup$