Can extrapolation to the basis set limit be an alternative to the counterpoise correction? A study on the helium dimer

Varandas, A. J. C.

doi:10.1007/s00214-008-0419-6

Cited by 41 publications

(63 citation statements)

References 56 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Although much larger basis sets and advanced techniques ͑often accompanied by correlation extrapolation to the CBS and FCI limits͒ are known to be required for high accuracy 76,77 ͑the list of references is by no means extensive; see also references therein͒, the results here reported may serve to illustrate the role of BSSE which is instead enhanced. Root I, yielding a large singlet weight, should therefore be preferred when dealing with strong interactions, while root II should describe better vdW interactions as it favors the triplet electron-pair excitations.…”

Section: From Sos To Sss: Rationalization Via Feenberg Scalingmentioning

confidence: 93%

Spin-component-scaling second-order Møller–Plesset theory and its variants for economical correlation energies: Unified theoretical interpretation and use for quartet N3

Varandas

2010

The Journal of Chemical Physics

Self Cite

View full text Add to dashboard Cite

The spin-component-scaling second-order Møller-Plesset theory proposed by Grimme, the scaled opposite-spin variant of Head-Gordon and co-workers, and other variants of the theory to treat the electron correlation energy are examined. A refinement of scaled opposite-spin theory for strong chemical interactions is suggested where the scaled correlation contribution is chosen such as to mimic closely the one obtained by more sophisticated methods of the coupled cluster type. With the scaling factor chosen to vary in a simple statistical manner with the number of opposite-spin electron pairs of the system, the parameters have been calibrated from standard coupled cluster type calculations for a chosen ab initio test data set. The new approach, termed as variable-scaling opposite spin, aims to be applicable at any regions of the molecule configuration space where second-order Møller-Plesset perturbation theory converges. It thus benefits of all advantages inherent to the original theory, which makes it an attractive approach on a computational cost basis. Because the method in one of its formats fails size-extensivity, the consequences and remedies of this are analyzed. Illustrations are presented for many molecules utilizing Dunning-type basis sets, in particular, for a detailed analysis of N(3) in its lowest quartet state, which does not belong to the test set. Extrapolations of the calculated raw energies to the complete one-electron basis set limit are also reported, giving the most reliable estimates available thus far of the energetics for the N((4)S)+N(2) exchange reaction. All spin-component-scaling schemes are known to show difficulties in dealing with weak interactions of the van der Waals type, which has justified the design of specific variants of the theory according to the property and regime of interactions. Several variants of the theory are then examined using a second test set of molecules, and shown to be linked via a coordinate that evolves gradually between two known extreme regimes. It is further shown that such a coordinate can be specified via a constrained Feenberg-type scaling approach, a theory whose merits are also explored.

show abstract

Section: From Sos To Sss: Rationalization Via Feenberg Scalingmentioning

confidence: 93%

Spin-component-scaling second-order Møller–Plesset theory and its variants for economical correlation energies: Unified theoretical interpretation and use for quartet N3

Varandas

2010

The Journal of Chemical Physics

Self Cite

View full text Add to dashboard Cite

show abstract

“…[ 5–14 ] The fragments cannot take advantage of the full dimer basis as the Pauli principle prevents them from using the occupied orbitals of the partner. [ 15–17 ] However, there appears to be a consensus that the CP method at least gives a correct estimate of BSSE. van Duijneveldt et al [ 18 ] argue that the CP method does provide a pure, BSSE‐free interaction energy at the full configuration interaction (CI) level.…”

Section: Introductionmentioning

confidence: 99%

Counterpoise correction is not useful for short and Van der Waals distances but may be useful at long range

et al. 2011

View full text Add to dashboard Cite

This article investigates the errors in supermolecule calculations for the helium dimer. In a full CI calculation, there are two errors. One is the basis set superposition error (BSSE), the other is the basis set convergence error (BSCE). Both of the errors arise from the incompleteness of the basis set. These two errors make opposite contributions to the interaction energies. The BSCE is by far the largest error in the short range and larger than (but much closer to) BSSE around the Van der Waals minimum. Only at the long range, the BSSE becomes the larger error. The BSCE and BSSE largely cancel each other over the Van der Waals well. Accordingly, it may be recommended to not include the BSSE for the calculation of the potential energy curve from short distance till well beyond the Van der Waals minimum, but it may be recommended to include the BSSE correction if an accurate tail behavior is required. Only if the calculation has used a very large basis set, one can refrain from including the counterpoise correction in the full potential range. These results are based on full CI calculations with the aug-cc-pVXZ (X = D, T, Q, 5) basis sets.

show abstract

“…[34,[41][42][43] The basis set superposition error [45] has been ignored in calculating the energetics. Indeed, use of the counterpoise technique [45] is deemed unjustified [16,46,47] due to employing CBS extrapolated energies. Counterpoise is not warranted with small basis functions, [48] such as DZ andT Z; CBS is the only logical and reliable alternative.…”

Section: Theorymentioning

confidence: 99%

“…Counterpoise is not warranted with small basis functions, [48] such as DZ andT Z; CBS is the only logical and reliable alternative. [16,46,47] All electronic structure calculations (M06-2X,C CSD(T), and MP2) for both direct and reverse reactions employed MOLPRO. [44] Notably,t he centralp rocessing unit (CPU) times always refer to the total time spent for two basis sets plus CBS extrapolation.…”

Section: Theorymentioning

confidence: 99%

Assessing How Correlated Molecular Orbital Calculations Can Perform versus Kohn–Sham DFT: Barrier Heights/Isomerizations

Varandas

González

Montero‐Cabrera

et al. 2017

Chemistry A European J

View full text Add to dashboard Cite

To assess the title issue, 38 hydrogen transfer barrier heights and 38 non-hydrogen transfer barrier heights/isomerizations extracted from extensive databases have been considered, in addition to 4 2 p-isomerization reactions and 6 others for large organic molecules. All Kohn-Sham DFT calculations have employed the popular M06-2X functional, whereas the correlated molecular orbital (MO)-based ones are from single-reference MP2 and CCSD(T) methods. They have all utilized the same basis sets, with raw MO energies subsequently extrapolated to the complete basis set limit without additional cost. MP2 calculations are found to be as cost-effective as DFT ones and often slightly more, while showing a satisfactory accuracy when compared with the reference data. Although the focus is on barrier heights, the results may bear broader implications, in that one may see successes and difficulties of DFT when compared with traditional MO theories for the same data.

show abstract

Can extrapolation to the basis set limit be an alternative to the counterpoise correction? A study on the helium dimer

Cited by 41 publications

References 56 publications

Spin-component-scaling second-order Møller–Plesset theory and its variants for economical correlation energies: Unified theoretical interpretation and use for quartet N3

Spin-component-scaling second-order Møller–Plesset theory and its variants for economical correlation energies: Unified theoretical interpretation and use for quartet N3

Counterpoise correction is not useful for short and Van der Waals distances but may be useful at long range

Assessing How Correlated Molecular Orbital Calculations Can Perform versus Kohn–Sham DFT: Barrier Heights/Isomerizations

Contact Info

Product

Resources

About