Hello,
I have been running some MP2 aug-cc-pVQZ, aug-cc-pVTZ and cc-pVTZ single point calculations, some of which are returning strange energies. An example of the type of output is shown below:
Total energy Delta E RMS
@DF-ROHF iter 0: -582.96967123898082 -5.82970e+02 0.00000e+00
@DF-ROHF iter 1: -138.94956589736944 4.44020e+02 0.00000e+00
@DF-ROHF iter 2: -138.94956589736944 0.00000e+00 0.00000e+00 DIIS
I’ve tried using canonical orbitals, and 3-21G, cc-pVDZ and cc-pVTZ basis set guesses, as well as gwh and sad.
Do you have any suggestions as to how I can get these calculations to converge? I’ve included an example input file below.
Thank you for your help.
David.
molecule complex {
0 2
C 0.299446 0.145069 0.025712
C 0.320471 0.165328 1.574454
C 1.781238 -0.061340 1.972966
C 1.758909 -0.006201 -0.396109
N 2.422185 -0.700513 0.766624
C 2.116510 -2.159187 0.739954
C 3.893116 -0.488533 0.756353
H 1.032411 -2.298019 0.779404
H 2.587221 -2.625504 1.608947
H 2.521753 -2.582747 -0.181859
H 4.304576 -0.954062 -0.143319
H 4.321887 -0.952096 1.649192
H 4.080079 0.588110 0.753293
H 1.925986 -0.723182 2.830469
H 2.301026 0.885885 2.130909
H -0.326524 -0.617315 1.981396
H -0.025973 1.123679 1.971456
H -0.305289 -0.689523 -0.342675
H -0.119181 1.066055 -0.389096
H 1.924692 -0.600093 -1.298226
H 2.246668 0.966568 -0.487488
N 2.375903 2.951944 0.911713
C 1.311220 3.441076 0.859309
N 0.177240 4.098386 0.811739
C -0.949999 3.433162 0.699065
N -2.000901 2.925452 0.594825
C -1.575354 -2.920804 0.925918
H -1.296743 -3.446389 0.017534
H -2.302464 -2.116091 0.879407
H -1.269567 -3.314237 1.890683
}
set globals {
basis aug-cc-pvqz
scf_type df
freeze_core True
guess gwh
basis_guess cc-pvdz
reference rohf
s_orthogonalization canonical
}
set cachelevel 0
set print 2
energy(‘df-mp2’)