Technically, I can calculate an electronic g-tensor for a S=1/2 system with a relativistic X2C Hamiltonian with DFT (PBE0, (all electron calc. for a 5d transition metal with corresponding all-electron X2C-TZVPALL basis set) .
I obtain strange results though, i.e. an isotropic value of 3 for g, where Orca gives 2.1…
Comments?
Hi Peter,
Can you post a sample input file? It can be for a different molecule if that’s sensitive information, but the $rem section should be the same as what you’re using.
$molecule
1 2
H -2.1665141986 -0.0000000000 3.6425713973
C -1.2148372780 0.0000000000 3.1071418134
C 1.1827725340 -0.0000000000 1.7131055748
C -1.1827725340 0.0000000000 1.7131055748
C 0.0000000000 0.0000000000 3.8006596474
C 1.2148372780 -0.0000000000 3.1071418134
N -0.0000000000 -0.0000000000 1.0601252719
H 0.0000000000 -0.0000000000 4.8924774064
H 2.1665141986 -0.0000000000 3.6425713973
C -2.2842838776 0.0000000000 0.7742305980
H -3.3314365153 0.0000000000 1.0929552966
C 2.2842838776 0.0000000000 0.7742305980
H 3.3314365153 0.0000000000 1.0929552966
N 1.9632769561 -0.0000000000 -0.4871047243
H 2.7335386973 -0.0000000000 -1.1551472661
N -1.9632769561 -0.0000000000 -0.4871047243
H -2.7335386973 -0.0000000000 -1.1551472661
Ir -0.0000000000 -0.0000000000 -1.0655665642
N 0.0000000000 -0.0000000000 -2.7144022975
$end
$rem
method PBE0
basis gen
REL_X2C 1
SYM_IGNORE = true
NO_REORIENT = true
SCF_CONVERGENCE = 10
SCF_GUESS GWH
THRESH 14
SCF_ALGORITHM DIIS
MAX_SCF_CYCLES 400
magnet true
$end
$magnet
hyperfine = true
gtensor = true
$end
$basis
H 0
pcseg-1
C 0
pcseg-1
N 0
pcseg-1
Ir 0
S 10 1.00
36869778.391 0.97951317695D-03
6600359.5318 0.26916421903D-02
1512277.3804 0.62232765746D-02
393794.13849 0.13886539954D-01
114453.49506 0.30422280943D-01
36319.237042 0.66508219163D-01
12411.946806 0.13919324545
4548.6251457 0.26653342789
1716.3516305 0.39347492163
646.20174021 0.27734585274
S 1 1.00
163.61330384 1.0000000000
S 5 1.00
13961.358935 -0.56613417772D-02
3359.3194039 -0.35065565663D-01
1163.2281883 -0.78387156844D-01
313.50124440 0.22721003807
92.559388737 0.43583988603
S 1 1.00
30.389393461 1.0000000000
S 1 1.00
17.080063536 1.0000000000
S 1 1.00
9.3003156110 1.0000000000
S 1 1.00
4.5752228910 1.0000000000
S 1 1.00
1.3740614625 1.0000000000
S 1 1.00
0.62300499776 1.0000000000
S 1 1.00
0.11680539930 1.0000000000
S 1 1.00
0.37459235070D-01 1.0000000000
P 8 1.00
2214367.7517 0.93473167909D-04
340671.96180 0.46592210302D-03
52068.438521 0.24499045489D-02
12230.432161 0.99899326258D-02
3711.8172073 0.37113517247D-01
1310.0756100 0.12193366283
516.51053052 0.29918708085
217.51662419 0.45298887081
P 1 1.00
249.36000000 1.0000000000
P 1 1.00
92.942883880 1.0000000000
P 5 1.00
7613.7481009 0.51541667077D-03
409.02287467 -0.19435664399D-01
70.402362508 0.30441227894
35.018754392 0.61085170146
16.948817848 0.30805961084
P 4 1.00
426.95723323 -0.35350518398D-02
11.775756099 0.49579723474
5.9417929894 0.62987578040
3.0336536159 0.21173092254
P 3 1.00
4.7336271097 -0.55123008016D-01
2.4740179307 0.25428871829
1.1260260799 0.64832326955
P 1 1.00
0.44801517114 1.0000000000
P 1 1.00
0.14200000000 1.0000000000
P 1 1.00
0.47500000000D-01 1.0000000000
D 6 1.00
2706.0973340 0.27936254972D-02
756.34433605 0.21405216578D-01
279.87064121 0.98668683084D-01
118.37407154 0.28106460401
53.427672621 0.45214224915
24.712400815 0.30451840314
D 1 1.00
42.060000000 1.0000000000
D 3 1.00
34.400533387 0.49777047852D-01
17.973676126 0.24218107183
9.0346747604 0.47997426458
D 1 1.00
4.2775505072 1.0000000000
D 1 1.00
1.6862093605 1.0000000000
D 1 1.00
0.63928186673 1.0000000000
D 1 1.00
0.20820882735 1.0000000000
D 1 1.00
0.67800000000D-01 1.0000000000
F 6 1.00
218.95239406 0.89498066994D-02
73.666664162 0.61124846007D-01
29.522285724 0.20728601997
12.656091196 0.38491296054
5.3493661284 0.41824893342
2.0966582826 0.23672674535
F 1 1.00
0.61008000000 1.0000000000
$end
$molecule
1 2
H -2.1665141986 -0.0000000000 3.6425713973
C -1.2148372780 0.0000000000 3.1071418134
C 1.1827725340 -0.0000000000 1.7131055748
C -1.1827725340 0.0000000000 1.7131055748
C 0.0000000000 0.0000000000 3.8006596474
C 1.2148372780 -0.0000000000 3.1071418134
N -0.0000000000 -0.0000000000 1.0601252719
H 0.0000000000 -0.0000000000 4.8924774064
H 2.1665141986 -0.0000000000 3.6425713973
C -2.2842838776 0.0000000000 0.7742305980
H -3.3314365153 0.0000000000 1.0929552966
C 2.2842838776 0.0000000000 0.7742305980
H 3.3314365153 0.0000000000 1.0929552966
N 1.9632769561 -0.0000000000 -0.4871047243
H 2.7335386973 -0.0000000000 -1.1551472661
N -1.9632769561 -0.0000000000 -0.4871047243
H -2.7335386973 -0.0000000000 -1.1551472661
Ir -0.0000000000 -0.0000000000 -1.0655665642
N 0.0000000000 -0.0000000000 -2.7144022975
$end
$rem
method PBE0
basis gen
REL_X2C 1
SYM_IGNORE = true
NO_REORIENT = true
SCF_CONVERGENCE = 10
SCF_GUESS GWH
THRESH 14
SCF_ALGORITHM DIIS
MAX_SCF_CYCLES 400
magnet true
$end
$magnet
hyperfine = true
gtensor = true
$end
$basis
H 0
pcseg-1
C 0
pcseg-1
N 0
pcseg-1
Ir 0
S 10 1.00
36869778.391 0.97951317695D-03
6600359.5318 0.26916421903D-02
1512277.3804 0.62232765746D-02
393794.13849 0.13886539954D-01
114453.49506 0.30422280943D-01
36319.237042 0.66508219163D-01
12411.946806 0.13919324545
4548.6251457 0.26653342789
1716.3516305 0.39347492163
646.20174021 0.27734585274
S 1 1.00
163.61330384 1.0000000000
S 5 1.00
13961.358935 -0.56613417772D-02
3359.3194039 -0.35065565663D-01
1163.2281883 -0.78387156844D-01
313.50124440 0.22721003807
92.559388737 0.43583988603
S 1 1.00
30.389393461 1.0000000000
S 1 1.00
17.080063536 1.0000000000
S 1 1.00
9.3003156110 1.0000000000
S 1 1.00
4.5752228910 1.0000000000
S 1 1.00
1.3740614625 1.0000000000
S 1 1.00
0.62300499776 1.0000000000
S 1 1.00
0.11680539930 1.0000000000
S 1 1.00
0.37459235070D-01 1.0000000000
P 8 1.00
2214367.7517 0.93473167909D-04
340671.96180 0.46592210302D-03
52068.438521 0.24499045489D-02
12230.432161 0.99899326258D-02
3711.8172073 0.37113517247D-01
1310.0756100 0.12193366283
516.51053052 0.29918708085
217.51662419 0.45298887081
P 1 1.00
249.36000000 1.0000000000
P 1 1.00
92.942883880 1.0000000000
P 5 1.00
7613.7481009 0.51541667077D-03
409.02287467 -0.19435664399D-01
70.402362508 0.30441227894
35.018754392 0.61085170146
16.948817848 0.30805961084
P 4 1.00
426.95723323 -0.35350518398D-02
11.775756099 0.49579723474
5.9417929894 0.62987578040
3.0336536159 0.21173092254
P 3 1.00
4.7336271097 -0.55123008016D-01
2.4740179307 0.25428871829
1.1260260799 0.64832326955
P 1 1.00
0.44801517114 1.0000000000
P 1 1.00
0.14200000000 1.0000000000
P 1 1.00
0.47500000000D-01 1.0000000000
D 6 1.00
2706.0973340 0.27936254972D-02
756.34433605 0.21405216578D-01
279.87064121 0.98668683084D-01
118.37407154 0.28106460401
53.427672621 0.45214224915
24.712400815 0.30451840314
D 1 1.00
42.060000000 1.0000000000
D 3 1.00
34.400533387 0.49777047852D-01
17.973676126 0.24218107183
9.0346747604 0.47997426458
D 1 1.00
4.2775505072 1.0000000000
D 1 1.00
1.6862093605 1.0000000000
D 1 1.00
0.63928186673 1.0000000000
D 1 1.00
0.20820882735 1.0000000000
D 1 1.00
0.67800000000D-01 1.0000000000
F 6 1.00
218.95239406 0.89498066994D-02
73.666664162 0.61124846007D-01
29.522285724 0.20728601997
12.656091196 0.38491296054
5.3493661284 0.41824893342
2.0966582826 0.23672674535
F 1 1.00
0.61008000000 1.0000000000
$end
Relativistic mass correction [ppm]
-171
One-electron gauge correction [ppm]
603 0 -0
0 587 -0
-0 0 384
Two-electron gauge correction [ppm]
-76 0 0
0 -68 -0
-0 -0 -79
One-electron spin-orbit+orbital-Zeeman contribution [ppm]
1378983 -0 0
-0 1267007 -0
-0 -0 861749
Two-electron spin-orbit+orbital-Zeeman contribution [ppm]
-13254 -0 0
-0 -10838 -0
-0 -0 -10702
Total shift [ppm]
1366084 -0 0
-0 1256517 -0
-0 -0 851181
The electronic g-matrix:
3.3684036 -0.0000000 0.0000000
-0.0000000 3.2588365 -0.0000000
-0.0000000 -0.0000000 2.8535002
gel 2.0023193 2.0023193 2.0023193
gRMC -0.0001714 -0.0001714 -0.0001714
gDSO(1el) 0.0003839 0.0005872 0.0006027
gDSO(2el) 0.0000675 0.0000762 0.0000792
gDSO(tot) 0.0004515 0.0006634 0.0006818
gPSO(1el) 0.8617491 1.2670073 1.3789828
gPSO(2el) 0.0107016 0.0108384 0.0132537
gPSO(tot) 0.8724508 1.2778457 1.3922365
g(tot) 2.8750502 3.2806570 3.3950663
Delta-g 0.8727309 1.2783377 1.3927470
Orientation:
X -0.0000000 -0.0000000 1.0000000
Y 0.0000000 -1.0000000 -0.0000000
Z 1.0000000 0.0000000 0.0000000
Thanks. Your input looks good, but gtensor = true is not documented in the manual (I’m not sure how you discovered it in the first place…) because as you note, the SOC term in particular is not correct. Q-Chem can still calculate the g-tensor at the CCSD level (see 10.12.4 Additional Magnetic Field-Related Properties‣ 10.12 NMR and Other Magnetic Properties ‣ Chapter 10 Molecular Properties and Analysis ‣ Q-Chem 6.0 User’s Manual), but I suspect that X2C will only be included to the effect of the modified molecular orbital coefficients entering the initial coupled cluster calculation. If there is a non-zero derivative of the X2C Hamiltonian with respect to B-field, it will not be accounted for.
I’ll disable this particular option for our upcoming release.