I’ve encountered a significant discrepancy in the atomic energies calculated for several transition metals (W, Re, Ir) using Psi4 at the wb97mv/def2-svpd level of theory. The issue seems to be specific to transition metals, as the calculations for organic molecules (e.g., H, C, O) yield consistent and accurate results when compared to other quantum chemistry packages like Jaguar.
Here’s a summary of the results for W:
Element
Molecule
Formula
Jaguar Atomic Energy (Ha)
Psi4 Atomic Energy (Ha)
Difference (Ha)
H
H2
H2
-0.5770035
-0.577114067
0.000110567
C
CH4
CH4
-38.135503
-38.13510729
-0.000395709
O
H2O
H2O
-75.193142
-75.19295249
-0.000189514
W
isolated
W
-66.62167
-66.68160669
0.059936688
W
REDNUK
C7H4O5W
-66.497504
-114.9241744
48.4266704
W
FERDIP-CO
C7H8O3W
-66.575713
-81.59841358
15.02270058
W
QAZWUJ-CO
C14H12O6W
-66.089077
-116.601408
50.51233104
W
XODDAW-CO
C34H34O5W
-65.2532444
-215.5008829
150.2476385
For organic molecules (H, C, O), the results agree with Jaguar and show minimal discrepancies. However, when it comes to tungsten and other transition metals like Re and Ir, the Psi4 energies are highly inconsistent and sometimes deviate by as much as 150 Hartree!
Sample Input File:
molecule FERDIP_CO {
0 1
W -0.05713407754315 -0.14864659018190 -0.15255709800078
O -1.69442143536118 -1.63857098157205 -2.33149248076233
C -1.07739031939630 -1.09829804926988 -1.52755770734550
C -1.31553100534254 1.64601071076200 0.49991460882643
H -0.82176552712375 2.58369265398967 0.24710740875750
H -1.61331095047414 1.55627615525433 1.54407417449809
C -2.08527618531366 1.01284435506803 -0.47146570867346
H -2.16105518211603 1.45330887519575 -1.46021534574177
H -2.94919653955078 0.43030814064546 -0.16873815447254
C -0.89579336113555 -1.23579074600505 1.28418668071446
O -1.29246802046766 -1.92572722812787 2.09833498026942
C 0.82025671115132 0.98986754269375 -1.52515066943175
O 1.40294885990693 1.57028068320966 -2.31239595904815
C 1.47043337808395 -1.65807330779779 0.57817639747092
H 1.22325885276241 -2.69061188659033 0.35051419646060
H 1.76002638587163 -1.48458376519588 1.61749901929082
C 2.07719007178722 -0.87156629156821 -0.41536041422695
H 2.28250492043074 -1.31787451836461 -1.38377338029728
H 2.80991017383053 -0.12417681214485 -0.10129088828741
}
set {
basis def2-SVPD
}
energy('wb97mv')
The only variation between calculations was the molecular coordinates, yet the issue persists across all transition metal-containing molecules. I have tested this with multiple structures, and the results are consistently off when Psi4 is used for these transition metals.
Has anyone else encountered this issue with transition metals? Is there a known fix or a specific setting that I might need to adjust? Any insights would be greatly appreciated.
What exactly are you calculating? You can calculate the energy of CH4, but how are you partitioning that into “the carbon contribution” and “the hydrogen contribution”? The same comment applies to your other molecules, but methane is a concrete example.
Basically, what I am trying to do is extract the atomic energies of different elements using “standard” molecules like H2 to extract the energy of H by dividing the total energy of H2 by 2. Using H atom’s energy, I extracted the energy of C from CH4 (subtracting 4*H from the total energy of the molecule). Same process for extracting the energy O from H2O.
Now having the “reference atomic energies” of C, H, and O, we can carry the same process to extract the energy of W of different organometallic molecules with the CSD_cod (i.e. mol_id): REDNUK, FERDIP, etc… What’s surprising is that the W atomic energy extracted from those different molecules is highly inconsistent and deviates by large amounts for the isolated W atomic energy.
I carried the same process using Jaguar software using the same set of molecules and the same level of theory, but the results were different, where W atomic energy stayed consistent and not deviating much from the isolated W atomic energy.
yea I could have computed H, C, and O from using single atom calculations, but I used stable molecules as a surrogate of “standard molecules” that are stable, from which we can obtain the atomic energies. In any case, the obtained atomic energies are generally close to their isolated energies counterparts and they should be more or less consistent across different molecular environments (with ± 2 Ha), as shown in Jaguar computations for W-containing molecules.
The compelling issue here is with W, where the atomic energy range can go from 66 Ha up to 215 Ha using Psi4 for the same set of W-molecules evaluated with Jaguar!
I would argue that the atomic energies are not close to your derived values. The energy of a hydrogen atom is -0.5 Eh, which means your energy of -0.577114067 Eh is off by more than 200 kJ/mol.
I can’t speak to why Jaguar is giving different energies for the molecules, but there are lots of potential parameters to adjust. If both codes are working correctly, you should be able to obtain identical results between the two of them, starting with H2.
Yes, I agree that the method of evaluating the atomic energies of elements could give different results, whether it is derived from a molecule or an isolated atom. The key is that if we stick to a certain method, we should at least expect consistent values (up to a certain threshold). I would be ok if the W atomic energies range from -64 to -67 Ha. As in the case of Jaguar, the range is from -65.25 to -66.6 Ha. However, the variation I see with Psi4 goes from -66 to -215!
As for the input parameters, I kept the input files consistent keeping everything set to default, only specifying the basis set and the density functional. Again, this is also how I did it with Jaguar.
What you’re telling us is that various linear combinations of single-point energies aren’t agreeing. This isn’t enough information for us to go on.
Give us the energies between Psi4 and Jaguar for all your single-points. If the disagreement is very specifically because Psi4 computes high energies for molecules containing tungsten, post your SCF iterations for those molecules.
Here is the output file for XODDAW-CO to view scf iterations XODDAW-CO.txt (49.7 KB)
As you can see in the scf iterations below, the initial guess for the electronic density is very close to the converged energy predicted by Jaguar (-1757.08282934246540), it then jumps to -1905.547 in the first iteration:
@DF-RKS iter SAD: -1757.08282934246540 -1.75708e+03 0.00000e+00 @DF-RKS iter 1: -1905.54724228132773 -1.48464e+02 1.72795e-03 DIIS @DF-RKS iter 2: -1840.99210992340477 6.45551e+01 9.32183e-03 DIIS @DF-RKS iter 3: -1906.86456210147776 -6.58725e+01 1.12896e-03 DIIS @DF-RKS iter 4: -1905.43782761383159 1.42673e+00 1.41857e-03 DIIS @DF-RKS iter 5: -1907.14387073606690 -1.70604e+00 7.92111e-04 DIIS @DF-RKS iter 6: -1907.59623588246905 -4.52365e-01 3.02615e-04 DIIS @DF-RKS iter 7: -1907.65609799190906 -5.98621e-02 1.81589e-04 DIIS @DF-RKS iter 8: -1907.68117150869693 -2.50735e-02 9.28408e-05 DIIS @DF-RKS iter 9: -1907.69392754935552 -1.27560e-02 3.66317e-05 DIIS @DF-RKS iter 10: -1907.69826762971411 -4.34008e-03 3.47514e-05 DIIS @DF-RKS iter 11: -1907.69946302303788 -1.19539e-03 3.33364e-05 DIIS @DF-RKS iter 12: -1907.70069366383132 -1.23064e-03 2.91722e-05 DIIS @DF-RKS iter 13: -1907.70192496526352 -1.23130e-03 1.98540e-05 DIIS @DF-RKS iter 14: -1907.70281339133498 -8.88426e-04 7.21430e-06 DIIS @DF-RKS iter 15: -1907.70312104075879 -3.07649e-04 4.69758e-06 DIIS @DF-RKS iter 16: -1907.70322082777989 -9.97870e-05 3.88449e-06 DIIS @DF-RKS iter 17: -1907.70326147746437 -4.06497e-05 2.70179e-06 DIIS @DF-RKS iter 18: -1907.70329555696367 -3.40795e-05 1.45785e-06 DIIS @DF-RKS iter 19: -1907.70330947615298 -1.39192e-05 1.02536e-06 DIIS @DF-RKS iter 20: -1907.70331574636748 -6.27021e-06 7.48315e-07 DIIS @DF-RKS iter 21: -1907.70331777531715 -2.02895e-06 4.16886e-07 DIIS @DF-RKS iter 22: -1907.70331933362831 -1.55831e-06 2.68930e-07 DIIS @DF-RKS iter 23: -1907.70331995425590 -6.20628e-07 1.73163e-07 DIIS
The Psi4 code is using density-fitting (DF), but we don’t know if Jaguar is doing the same. Furthermore, we don’t know the definition(s) of Jaguar’s integration grids to compare with those of Psi4. There are multiple ways that the codes could differ, and we don’t have any knowledge here of Jaguar’s internals. (At least, I don’t.)
Psi4 having lower single points than Jaguar is not what I was expecting.
Can you repeat the tungsten single points using Hartree-Fock using both Jaguar and Psi4? My intuition is that you’re having problems with multiple SCF solutions, and that’s easier to analyze at the Hartree-Fock level than DFT. I’d also strongly advise you to use a more recent version of Psi4.