Linear scaling explicitly correlated MP2-F12 and ONIOM methods for the long-range interactions of the nanoscale clusters in methanol aqueous solutions

Li, Wei

doi:10.1063/1.4773011

Cited by 30 publications

(29 citation statements)

References 103 publications

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“…[135][136][137][138][139] The combination of explicitly correlated approaches with local methods has been particularly successful. 49,50,53,76,135,[140][141][142][143][144][145][146][147] It has been found that the F12 terms not only reduce the basis set incompleteness errors, but also implicitly account for excitations to the orbitals outside the domains, 140,141 and therefore reduce the domain errors significantly. This strongly improves the accuracy and robustness of the local methods.…”

Section: Introductionmentioning

confidence: 99%

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Explicitly correlated local coupled‐cluster methods using pair natural orbitals

Werner

2018

WIREs Comput Mol Sci

205

263

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Recently developed explicitly correlated local coupled-cluster methods [PNO-LCCSD(T)-F12] are reviewed. Extensive benchmarks for reaction energies and intermolecular interaction energies are presented, in which the convergence of the results with respect to all local approximations is studied. The explicit correlation treatment (F12) is shown to be essential to minimize basis set incompleteness errors, as well as errors caused by domain approximations. Generally, the errors of relative energies due to local approximations can be reduced to below 1 kcal/mol. The methods are well parallelized, and using small computer clusters with 100-200 computing cores, calculations for systems with 100-200 atoms using augmented triple-ζ basis sets can be carried out within a few hours of elapsed time. Recommendations are made on how such calculations should be carried out, how the accuracy can be tested, and which computational resources are required. This article is categorized under: Electronic Structure Theory> Ab Initio Electronic Structure Methods Software> Quantum Chemistry K E Y W O R D S explicit correlation, coupled cluster, local correlation, pair natural orbitals 1 | INTRODUCTIONThe coupled-cluster method with single and double excitations and a perturbative treatment of triple excitations [CCSD(T)] is considered the gold standard of quantum chemistry for computing energies and other properties of molecules. Often, the accuracy is comparable or even better than that of experimental data, and chemical accuracy (1 kcal/mol or better for relative energies) can be achieved, provided that the system under consideration is of single-reference character, that is, the Hartree-Fock (HF) Slater determinant dominates the total wave function expansion. However, in its traditional canonical form, the application of the CCSD(T) method is limited to rather small systems (20-30 atoms) due to the steep increase of the computational effort with system size: The central processing unit (CPU) time scales as O N 7 el

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Section: Introductionmentioning

confidence: 99%

“…The combination of explicitly correlated approaches with local methods has been particularly successful . It has been found that the F12 terms not only reduce the basis set incompleteness errors, but also implicitly account for excitations to the orbitals outside the domains, , and therefore reduce the domain errors significantly.…”

Section: Introductionmentioning

confidence: 99%

Explicitly correlated local coupled‐cluster methods using pair natural orbitals

Werner

2018

WIREs Comput Mol Sci

205

263

View full text Add to dashboard Cite

show abstract

“…In the GEBF approach, the ground‐state energy of a target system can be obtained from the energies of a series of subsystems, each of which is embedded in the field of natural population analysis (NPA) point charges on the atoms outside of the subsystem to take the long‐range electrostatic interactions and polarization effects into account. Then, the total energy of the target system can be represented as,

E_{tot} = \sum_{m}^{M} C_{m} {\overset{E}{true}}_{m} - true(\sum_{m}^{M} C_{m} - 1 true) \sum_{A} \sum_{B > A} \frac{Q_{A} Q_{B}}{| {boldq}_{A} - {boldq}_{B} |}

where

M

is the number of subsystems,

C_{m}

and

{\overset{E}{true}}_{m}

are the coefficients and the energy (including self‐energy of point charges) of the

m

th embedded subsystems, respectively, and

{boldq}_{A}

and

Q_{A}

are the coordinates of atom

A

and the point charge located on atom

A

, respectively.…”

Section: Methodsmentioning

confidence: 99%

“…To reduce the scalings of the conventional quantum chemistry methods, three categories of linear scaling algorithms have been implemented, including first‐principle linear scaling HF and DFT algorithms, local correlation post‐HF methods, and fragmentation‐based approaches . The first‐principle linear HF and DFT algorithms focus on the fast algorithms of integrals, Coulomb and exchange matrices, or the avoidance of the diagonalization of Fock matrices.…”

Section: Introductionmentioning

confidence: 99%

“…The basic idea of the GEBF approach is that the energy or energy derivatives of a large system can be approximately obtained from the energies and energy derivatives of a series valence saturated subsystems, each of which is embedded in the field of point charges on those atoms outside of the subsystem. The GEBF method has been used to compute the ground‐state energies, molecular geometries, vibrational spectra, and molecular properties of general large systems at various levels of ab initio and DFT methods . Conversely, to treat more general large systems, which cannot be treated with the GEBF approach, Li et al have also developed a local correlation method, cluster‐in‐molecule (CIM), in 2002 and then improve it in 2006 .…”

Section: Introductionmentioning

confidence: 99%

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LSQC: Low scaling quantum chemistry program

Chen

Zhao

et al. 2014

Int J of Quantum Chemistry

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A low scaling quantum chemistry program, called LSQC, is described in this article. This version includes two linear scaling methods, generalized energy-based fragmentation (GEBF) approach and cluster-in-molecule (CIM) approach. In the GEBF approach, a variety of electron structure methods (including ab initio and density functional theory) are available for the calculations of ground-state energies, geometry optimizations, vibrational spectra, and other molecular properties for large systems. In the CIM approach, the electron correlation energies of large systems can be approximately obtained at the second-order Møller2Plesset perturbation theory and couple cluster levels. In this article, the details and the capabilities of the LSQC program are presented.

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Breaking a bottleneck: Accurate extrapolation to “gold standard” CCSD(T) energies for large open shell organic radicals at reduced computational cost

2015

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Open Shell organic radicals are principal species involved in many diverse areas such as combustion, photochemistry, and polymer chemistry. Computational studies of such species with an accurate method like coupled-cluster with single and double and perturbative triple (CCSD(T)) may be restricted to systems of modest size due to the steep computational scaling of the method. Herein, we assess the accuracy of extrapolated CCSD(T) energies determined using the connectivity-based hierarchy (CBH) method on medium to large sized radicals. In our method, an MP2 calculation on the target radical is coupled with CCSD(T) energies of fragments determined uniquely by our hierarchy to perform accurate extrapolations. A careful assessment is done with a robust CBH-rad49 test set comprising of 49 diverse cyclic and acyclic radicals with a variety of functional groups. We demonstrate that the extrapolation method with CBH-2 or CBH-3 is sufficient to obtain sub-kcal accuracy. ROMP2 and PMP2 calculations with both Pople-style and Dunning-style basis-sets resulted in mean absolute errors for CCSD(T) extrapolation (full CCSD(T)-extrapolated CCSD(T)) within 0.5 kcal/mol. Further speedup for such CCSD(T) extrapolations are obtained with ROHF-based RI-MP2 calculations. Challenging systems with (a) high ring strain, (b) delocalized character, and (c) spin contamination are identified and analyzed in detail. Finally, we apply our extrapolation method on 10 larger radicals containing 10-15 heavy atoms, where accurate CCSD(T) energies are obtained at a fractional cost of full CCSD(T) calculations.

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Linear scaling explicitly correlated MP2-F12 and ONIOM methods for the long-range interactions of the nanoscale clusters in methanol aqueous solutions

Cited by 30 publications

References 103 publications

Explicitly correlated local coupled‐cluster methods using pair natural orbitals

Explicitly correlated local coupled‐cluster methods using pair natural orbitals

LSQC: Low scaling quantum chemistry program

Breaking a bottleneck: Accurate extrapolation to “gold standard” CCSD(T) energies for large open shell organic radicals at reduced computational cost

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