Question for Standard nuclear orientation

Hello guys.

I have tried to make a python file that can import xyz coordinates from output file after geometry optimization and create a new input file automatically to do other jobs (like sp calculation) using the optimized coordinates.

So I wrote codes and got a new input file, but there was a problem.

When I submitted it to Qchem program and the calculation was proceeded, there was a change in coordinates represented by ‘Standard Nuclear Orientation’. You can check it below.

I think the input file is ok as the coordinates don’t need to be arranged clearly if there is a blank between the coordinates.

But I have never seen this situation when I made a new input file from the optimized output file by handmade.

So I wonder whether it is ok to continue the calculation.

A new input file by a python programming

$molecule
0 1
N 6.0382993654 3.8132988997 -0.4555276482
C 4.9864438977 4.2990168568 -1.2164856476
C 3.9135235709 3.3203534079 -1.5135810805
C 6.2027919159 2.5279327012 0.0497140536
C 5.1058348486 1.5837543099 -0.2617172763
C 3.9948849765 1.9890998611 -1.0403906428
C 2.8320071623 3.7259003188 -2.2592401065
C 1.7886156335 2.8356409139 -2.516702544
C 1.8084135217 1.5375556778 -2.0293002957
C 2.9453649299 1.0716740171 -1.3135139273
C 5.1566983114 0.3067862381 0.2296411736
C 4.147074806 -0.6152445182 -0.0738308777
C 3.0423250546 -0.280151331 -0.8416821219
C 0.6727859737 0.6324026277 -2.217618243
C 1.9839069919 -1.2445207727 -1.2165475546
C 0.8211365828 -0.7516093271 -1.9044779455
C -0.5480608552 1.1057017094 -2.6701516749
C -1.6273484195 0.2504507052 -2.8872355459
C -0.256459703 -1.6222624821 -2.2082540885
C 1.9911248557 -2.6026791737 -0.90334138
C 0.9917942632 -3.4849244248 -1.3465030731
C -0.1292851681 -3.0112818308 -1.963350785
C -1.4814419795 -1.0986847745 -2.6820298962
C -2.6534304523 -1.9796217269 -2.8708260323
C -1.2568990353 -3.9339521378 -2.2299970739
N -2.4003588258 -3.3366134103 -2.7389833066
O 7.187457522 2.2366236716 0.6960901489
O 4.967767673 5.45368651 -1.5946968519
O -3.7720239694 -1.5729018426 -3.1167881429
O -1.2302107648 -5.1278477665 -2.0019698761
H 6.7815402338 4.4712601056 -0.2487632572
H 2.8072494334 4.7450428287 -2.6294787263
H 0.953608376 3.1836858311 -3.1091982696
H 5.9916045077 0.0173947697 0.8566145453
H 4.26728753 -1.611330997 0.3003439625
H -0.6987969327 2.164458991 -2.8268313571
H -2.5891984214 0.6291628631 -3.2093196846
H 1.0725828682 -4.5372402981 -1.1030151135
H -3.2132860161 -3.9363849536 -2.8190094683
O 2.9967859427 -3.1774228083 -0.1681547536
C 2.9372683697 -3.3648715769 1.2052601635
C 1.7907175585 -3.387381658 2.0124859029
C 4.1972117012 -3.5869911348 1.7617058802
C 1.9717044361 -3.6599645886 3.3749736509
C 3.2219346991 -3.8639567303 3.9364124897
C 4.346004339 -3.8255437963 3.1178826261
C 0.3895750229 -3.2152747694 1.5486932098
C -0.0975345503 -2.0018920797 1.0738562331
C -1.3965979842 -1.8952418142 0.6110191647
C -2.2815189885 -2.9712117596 0.6801562868
C -1.8028690037 -4.1755254266 1.2045059532
C -0.4855694029 -4.2998545915 1.6181275927
C -3.6856465848 -2.8876285565 0.2143649572
C -4.5110379454 -1.7725490266 0.407255902
C -5.8577209627 -1.7964586336 0.0661303734
C -6.400163198 -2.9129573339 -0.5527366147
C -5.5931029578 -4.0187472822 -0.7995955872
C -4.2641490095 -4.0043307753 -0.4046360805
H 5.0550568958 -3.5746533822 1.0975939804
H 1.0912466373 -3.6731930294 4.0071955709
H 3.3111621181 -4.0537454577 5.0011552236
H 5.3378681956 -3.984363941 3.528232073
H 0.5612381779 -1.1470785777 1.0125940681
H -1.7072505198 -0.9747473842 0.1463195757
H -2.4702067514 -5.0263979567 1.2858619407
H -0.123383932 -5.2498207328 1.9976248857
H -6.4700367876 -0.9313139214 0.2942544295
H -7.4468788649 -2.9172171802 -0.8371103543
H -6.0020525415 -4.8965600288 -1.2893789694
H -3.630734832 -4.8647852684 -0.5999721526
O -4.0060384309 -0.6515767656 1.0590036336
C -3.6756609604 0.4735514263 0.3516170311
C -2.5721098742 1.2233764147 0.7686032844
C -2.1567711881 2.3126692428 -0.0601552945
C -2.9726828614 2.7442412178 -1.1322928478
C -4.1284224047 1.9990542601 -1.4567505869
C -4.4361581255 0.8590041469 -0.7668496144
C -0.8817533227 2.9307454454 0.1109732704
C -0.558783657 4.0421946755 -0.6509298166
C -1.4166382679 4.5203097381 -1.6466942465
C -2.5925085829 3.8590501353 -1.9145855114
C -3.4352541736 4.3016834153 -3.0491560755
C -4.9963578036 2.4061340635 -2.5879080089
N -4.561764824 3.5244159522 -3.2896046009
C 0.0862196254 2.3003508685 1.0137024773
C -0.376377243 1.3048611061 1.9201057215
C -1.7350140657 0.8655530115 1.9244483001
C 1.4359670655 2.606124878 0.9751073821
C 2.3546851753 1.932718687 1.7860158936
C 1.9244045755 0.9897659275 2.6865885468
C 0.544781345 0.7049851198 2.812812949
C 0.0842354483 -0.2122601514 3.7861639736
C -1.25891923 -0.4763374659 3.8920462814
C -2.1631560113 0.0485179955 2.9593819057
C 2.9180279833 0.2193167106 3.46630488
C 1.0465523923 -0.9155681371 4.6608810778
N 2.3845223793 -0.6374805482 4.4182023313
O 4.1194220408 0.2972392573 3.2972314514
O 0.7252771632 -1.719289917 5.5159059343
O -3.179844293 5.2621980191 -3.7468752787
O -6.0152541218 1.8278608728 -2.9021629924
H -5.2757379615 0.2684747299 -1.1048659625
H 0.3879169386 4.5442279444 -0.4991948076
H -1.1542115704 5.383479677 -2.2486428283
H -5.1474486 3.8182642589 -4.0635256955
H 1.8151830895 3.3276087566 0.2638920674
H 3.4173518668 2.1215947442 1.6995979955
H -1.5965022542 -1.1540884994 4.6681488921
H -3.1989463728 -0.2459296266 3.0166902439
H 3.0522536717 -1.2148673956 4.9165386129
$end

$rem
   BASIS  =  6-31G*
   JOB_TYPE  =  Optimization
   exchange  =  CAMB3LYP
   DFT_D  =  EMPIRICAL_GRIMME
   SCF_CONVERGENCE  =  8
   scf_algorithm rca_diis
   SCF_MAX_cycles 512
   MEM_TOTAL = 8000
   GUI = 0
   GEOM_OPT_MAX_CYCLES = 500
   XC_GRID = 75000302
   THRESH = 14
$end

$empirical_dispersion
   S6 1.0
$end

Standard Nuclear Orientation from a new calculation

 ----------------------------------------------------------------
             Standard Nuclear Orientation (Angstroms)
    I     Atom           X                Y                Z
 ----------------------------------------------------------------
    1      N       6.2330866618     3.5428516533    -0.5226915966
    2      C       5.1079073060     4.3448621955    -0.6328253476
    3      C       3.8540971913     3.6344975881    -0.9800258529
    4      C       6.3201953323     2.1666051493    -0.7039397154
    5      C       5.0451707248     1.4938942940    -1.0409107393
    6      C       3.8463988049     2.2339323956    -1.1828133053
    7      C       2.6920841508     4.3589102690    -1.1029298133
    8      C       1.4907940813     3.7080735005    -1.3872329381
    9      C       1.4335099651     2.3315155548    -1.5446652743
   10      C       2.6308522448     1.5663554748    -1.4902973716
   11      C       5.0218227922     0.1336487998    -1.1953605500
   12      C       3.8354917243    -0.5247452991    -1.5427960575
   13      C       2.6343895414     0.1478821688    -1.7079651408
   14      C       0.1603770115     1.6372726750    -1.7485645811
   15      C       1.3760877798    -0.5141589590    -2.1192552210
   16      C       0.1658052745     0.2625892744    -2.1303628552
   17      C      -1.0460688431     2.2889950531    -1.5510504061
   18      C      -2.2653193920     1.6512270880    -1.7749286215
   19      C      -1.0771705690    -0.3488251451    -2.4348527182
   20      C       1.2513310269    -1.8632877939    -2.4464120440
   21      C       0.0441681300    -2.4220743644    -2.8979936110
   22      C      -1.1107086856    -1.6960311299    -2.8700962947
   23      C      -2.2852272857     0.3573706864    -2.2322073968
   24      C      -3.5892605332    -0.3144928519    -2.4148205151
   25      C      -2.3996755393    -2.3697784354    -3.1503868413
   26      N      -3.5278262352    -1.5834490459    -2.9705454345
   27      O       7.3818595081     1.5911748036    -0.5857091857
   28      O       5.1724694381     5.5437925666    -0.4456029645
   29      O      -4.6543500376     0.1808495653    -2.1027466169
   30      O      -2.5024833261    -3.5342730246    -3.4842705780
   31      H       7.0987334806     4.0167760333    -0.2900486996
   32      H       2.7315747012     5.4340963850    -0.9659759937
   33      H       0.5947147989     4.3061056839    -1.4811637460
   34      H       5.9361724706    -0.4282967149    -1.0467224270
   35      H       3.8915025080    -1.5831039681    -1.6957205594
   36      H      -1.0637691351     3.3030405810    -1.1773724215
   37      H      -3.2058042066     2.1539407659    -1.5876219515
   38      H       0.0192664991    -3.4691864397    -3.1738886867
   39      H      -4.4171094035    -2.0630016030    -3.0491933781
   40      O       2.3116976022    -2.7314659755    -2.3825903078
   41      C       2.5883273260    -3.5309392106    -1.2829237860
   42      C       1.7071320012    -3.9021477761    -0.2570593401
   43      C       3.8990710560    -4.0086662209    -1.2953298363
   44      C       2.1962693395    -4.7765975869     0.7224878818
   45      C       3.5019517717    -5.2403736860     0.7251693604
   46      C       4.3612806425    -4.8494185033    -0.2964505216
   47      C       0.2786261441    -3.5089038479    -0.1445645525
   48      C      -0.1187710767    -2.2044512857     0.1302488467
   49      C      -1.4602312186    -1.8716150789     0.1837557001
   50      C      -2.4537692199    -2.8409697723     0.0466055367
   51      C      -2.0499087007    -4.1600909308    -0.1797478139
   52      C      -0.7068902108    -4.4862147549    -0.2882071485
   53      C      -3.8996158154    -2.5252432641     0.1198613588
   54      C      -4.4579845429    -1.6100063950     1.0212192292
   55      C      -5.8332053946    -1.4482627966     1.1356747312
   56      C      -6.6890485613    -2.1422221511     0.2932008955
   57      C      -6.1609129579    -3.0239484362    -0.6441829832
   58      C      -4.7898365954    -3.2186415734    -0.7117376629
   59      H       4.5417765214    -3.7071408467    -2.1157610320
   60      H       1.5234830604    -5.0637566775     1.5224777334
   61      H       3.8381893008    -5.9021499587     1.5167847163
   62      H       5.3883492819    -5.1984819873    -0.3227014473
   63      H       0.6267676301    -1.4305786480     0.2474404030
   64      H      -1.7332865117    -0.8348840746     0.2856886843
   65      H      -2.7976660675    -4.9395888644    -0.2755831975
   66      H      -0.4119646187    -5.5106956913    -0.4909135533
   67      H      -6.2189810656    -0.7749410528     1.8928151332
   68      H      -7.7607655318    -1.9949212391     0.3721023147
   69      H      -6.8179653524    -3.5683964695    -1.3146613434
   70      H      -4.3745839095    -3.9033466815    -1.4455603648
   71      O      -3.6283739436    -0.9265620967     1.9049774370
   72      C      -3.3233271723     0.3916401351     1.6934405137
   73      C      -2.0448184152     0.8431315722     2.0333094425
   74      C      -1.6966556272     2.1840177328     1.6773419594
   75      C      -2.6880998677     3.0773019360     1.2077391361
   76      C      -3.9910868351     2.5881679819     0.9642576050
   77      C      -4.2815655667     1.2643838681     1.1475513940
   78      C      -0.3407507519     2.6290129748     1.6991350448
   79      C      -0.0593141717     3.9604063022     1.4377725204
   80      C      -1.0631422084     4.8604756299     1.0659394606
   81      C      -2.3570914703     4.4200142334     0.9130013825
   82      C      -3.3888156993     5.3524502714     0.4035871438
   83      C      -5.0514883467     3.4879757963     0.4500227678
   84      N      -4.6468613321     4.7955149243     0.2083164264
   85      C       0.7192363407     1.6348099329     1.8922066555
   86      C       0.3614278966     0.3421287118     2.3691877333
   87      C      -0.9994628799    -0.0238209335     2.5993216673
   88      C       2.0415429725     1.8983392513     1.5777818662
   89      C       3.0236184773     0.9093364880     1.6895526790
   90      C       2.7033099056    -0.3346743527     2.1744978840
   91      C       1.3790419848    -0.6195010954     2.5814145427
   92      C       1.0532221204    -1.8737620866     3.1484457670
   93      C      -0.2384535769    -2.1315216780     3.5359328857
   94      C      -1.2623646910    -1.2182777937     3.2520810087
   95      C       3.7330973729    -1.3967323976     2.1946848611
   96      C       2.0889185224    -2.9195744946     3.2878566924
   97      N       3.3417319773    -2.5861077867     2.7922280319
   98      O       4.8438153731    -1.2721828142     1.7163561517
   99      O       1.8822677134    -4.0211405570     3.7612504301
  100      O      -3.1785265683     6.5216317502     0.1517384814
  101      O      -6.1952324582     3.1395581337     0.2456693367
  102      H      -5.2629080709     0.9126941239     0.8626732478
  103      H       0.9607679247     4.3176478382     1.4935751675
  104      H      -0.8362397823     5.8989698912     0.8507252226
  105      H      -5.3622031159     5.4245904873    -0.1393561809
  106      H       2.3283355059     2.8594649441     1.1726171476
  107      H       4.0416917721     1.0967081991     1.3720289420
  108      H      -0.4615882050    -3.0846239780     4.0022492670
  109      H      -2.2792199229    -1.4863241190     3.4908317691
  110      H       4.0175783311    -3.3408603659     2.7581699923
 ----------------------------------------------------------------

So the standard nuclear orientation is only translating and rotating the input. This is done by default to move input molecules to the origin for example. The structures should be identical if the python script is working as intended. The way to check is to look at the Nuclear Repulsion Energy for the optimized structure from the optimization job and the first Nuclear Repulsion Energy in the second job, they should be identical.

In addition, you can use SYM_IGNORE = TRUE will turn of symmetry but also not perform the standard nuclear orientation.

1 Like

I understand. Thank you for answering it for me :slight_smile:

I believe that you can use NO_REORIENT=TRUE to force Q-Chem to use the input coordinates as given, without disabling symmetry. The idea behind rotating into the SNO is to hide the fact that DFT energies may not be rotationally invariant. That way an input file generated with two different GUIs, which might use different laboratory-fixed frames, would produce the same energy because Q-Chem rotates them into the same frame.

1 Like

I appreciate with your comment. It’s a new option that I can utilize well.