Quelling the Geometry Factor Effect in Quantum Chemical Calculations of 13C NMR Chemical Shifts with the Aid of the pecG-n (n = 1, 2) Basis Sets
Abstract
:1. Introduction
2. Results and Discussion
2.1. The PEC Method and the pecG-n (n = 1, 2) Basis Sets
2.2. Theoretical Analysis of the pecG-n (n = 1, 2) Basis Sets
2.3. Analysis of the Performance of the pecG-n (n = 1, 2) Basis Sets Based on a Comparison of the Theoretical Data with Experimental Data
3. Materials and Methods
4. Conclusions
Supplementary Materials
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Basis Set | Element | Contracted Composition | Number of Contracted Basis Functions |
---|---|---|---|
Rusakov’s pecG-n series | |||
pecG-1 | H | [2s2p] | 8 |
B-F | [3s2p2d] | 19 | |
pecG-2 | H | [3s3p1d] | 17 |
B-F | [4s3p3d1f] | 35 | |
Dunning’s cc-pVXZ series | |||
cc-pVDZ | H | [2s1p] | 5 |
B-F | [3s2p1d] | 14 | |
cc-pVTZ | H | [3s2p1d] | 14 |
B-F | [4s3p2d1f] | 30 | |
cc-pVQZ | H | [4s3p2d1f] | 30 |
B-F | [5s4p3d2f1g] | 55 | |
Pople-style K-LMNG(x,y) series | |||
6-311G(d,p) | H | [3s1p] | 6 |
B-F | [4s3p1d] | 18 | |
6-31G(2d,2p) | H | [2s2p] | 8 |
B-F | [3s2p2d] | 19 | |
6-311G(3df,3pd) | H | [3s3p1d] | 17 |
B-F | [4s3p3d1f] | 35 |
Molecule | No. of Carbon Atoms 1 | 6-311G(d,p) | 6-31G(2d,2p) | 6-311G(3df,3pd) | pecG-1 | pecG-2 | Exp. 2 |
---|---|---|---|---|---|---|---|
Acetaldehyde | 1 | 196.19 | 197.17 | 196.25 | 196.37 | 196.97 | 199.97 |
2 | 34.92 | 34.70 | 35.09 | 34.90 | 35.02 | 30.99 | |
Acetonitrile | 1 | 4.95 | 4.84 | 4.85 | 4.61 | 4.65 | 1.91 |
2 | 115.07 | 115.73 | 115.57 | 115.91 | 115.93 | 116.33 | |
Cyclopropane | −1.61 | −1.66 | −1.37 | −1.63 | −1.57 | −3.15 | |
DMAc | 1 | 160.74 | 161.03 | 161.06 | 160.69 | 161.50 | 170.66 |
2 | 25.58 | 25.25 | 26.12 | 25.34 | 26.10 | 21.58 | |
3 | 40.35 | 39.75 | 40.60 | 39.86 | 40.61 | 38.05 | |
4 | 34.32 | 33.74 | 34.61 | 33.88 | 34.60 | 35.20 | |
Fluorobenzene | 1 | 155.98 | 156.06 | 155.61 | 156.09 | 155.93 | 162.86 |
2 | 111.85 | 111.65 | 111.51 | 111.72 | 111.49 | 115.32 | |
3 | 131.15 | 130.89 | 131.09 | 131.00 | 130.94 | 129.96 | |
4 | 127.11 | 126.88 | 126.52 | 126.89 | 126.55 | 123.98 | |
Isoxazole | 1 | 158.00 | 158.72 | 157.55 | 158.28 | 157.62 | 157.64 |
2 | 106.04 | 105.96 | 105.78 | 105.95 | 105.65 | 103.47 | |
3 | 148.72 | 149.18 | 148.16 | 148.83 | 147.96 | 149.02 | |
Norbornadiene | 1 | 145.04 | 145.27 | 145.17 | 145.05 | 144.97 | 143.43 |
2 | 48.28 | 48.27 | 48.29 | 48.63 | 48.27 | 50.26 | |
3 | 74.67 | 74.19 | 75.34 | 75.13 | 75.50 | 75.32 | |
Oxetane | 1 | 73.80 | 74.05 | 73.96 | 73.87 | 73.94 | 72.55 |
2 | 23.41 | 23.09 | 23.46 | 23.41 | 22.91 | 22.35 | |
Pyridine | 1 | 150.18 | 150.07 | 149.91 | 150.29 | 149.98 | 149.74 |
2 | 125.15 | 124.97 | 124.99 | 124.95 | 124.69 | 123.78 | |
3 | 137.53 | 137.41 | 137.21 | 137.33 | 137.11 | 136.09 | |
α | 196.12 | 196.82 | 197.81 | 197.18 | 198.54 | ||
MAE | 2.43 | 2.34 | 2.39 | 2.31 | 2.25 |
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Rusakov, Y.Y.; Semenov, V.A.; Rusakova, I.L. Quelling the Geometry Factor Effect in Quantum Chemical Calculations of 13C NMR Chemical Shifts with the Aid of the pecG-n (n = 1, 2) Basis Sets. Int. J. Mol. Sci. 2024, 25, 10588. https://doi.org/10.3390/ijms251910588
Rusakov YY, Semenov VA, Rusakova IL. Quelling the Geometry Factor Effect in Quantum Chemical Calculations of 13C NMR Chemical Shifts with the Aid of the pecG-n (n = 1, 2) Basis Sets. International Journal of Molecular Sciences. 2024; 25(19):10588. https://doi.org/10.3390/ijms251910588
Chicago/Turabian StyleRusakov, Yuriy Yu., Valentin A. Semenov, and Irina L. Rusakova. 2024. "Quelling the Geometry Factor Effect in Quantum Chemical Calculations of 13C NMR Chemical Shifts with the Aid of the pecG-n (n = 1, 2) Basis Sets" International Journal of Molecular Sciences 25, no. 19: 10588. https://doi.org/10.3390/ijms251910588