Performance of the NOF-MP2 method in hydrogen abstraction reactions

López, Xabier; Piris, Mario

doi:10.1007/s00214-019-2475-5

Cited by 11 publications

(6 citation statements)

References 46 publications

(65 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The reformulation of NOF-MP2 based on the static part of PNOF7 (PNOF7s) and the orbital-invariant MP2 allowed us to prevent reference ONs and NOs from being spuriously influenced by nondynamic correlation in dynamic correlation domains and extend the NOF-MP2 method to any type of orbitals, including localized ones, respectively. NOF-MP2 has been shown to provide quantitative agreement for dissociation energies, with performance comparable to that of the accurate complete active space second-order perturbation theory in hydrogen abstraction reactions, and is highly reliable for accurate chemical reaction mechanistic studies in elementary reactions of transition metal compounds …”

Section: Introductionmentioning

confidence: 99%

Electron Correlation in the Iron(II) Porphyrin by Natural Orbital Functional Approximations

Lew-Yee

Campo

Piris

2022

J. Chem. Theory Comput.

Self Cite

View full text Add to dashboard Cite

The relative stability of the singlet, triplet, and quintet spin states of iron(II) porphyrin (FeP) represents a challenging problem for electronic structure methods. While it is currently accepted that the ground state is a triplet, multiconfigurational wave function-based methods predict a quintet, and density functional approximations vary between triplet and quintet states, leading to a prediction that highly depends on the features of the method employed. The recently proposed Global Natural Orbital Functional (GNOF) aims to provide a balanced treatment between static and dynamic correlation, and together with the previous Piris Natural Orbital Functionals (PNOFs), allowed us to explore the importance of each type of correlation in the stability order of the states of FeP with a method that conserves the spin of the system. It is noteworthy that GNOF correlates all electrons in all available orbitals for a given basis set; in the case of the FeP with a double-ζ basis set as used in this work, this means that GNOF can properly correlate 186 electrons in 465 orbitals, significantly increasing the sizes of systems amenable to multiconfigurational treatment. Results show that PNOF5, PNOF7s, and PNOF7 predict the quintet to have a lower energy than the triplet state; however, the addition of dynamic correlation via secondorder Møller−Plesset corrections (NOF-MP2) turns the triplet state to be lower than the quintet state, a prediction also reproduced by GNOF that incorporates much more dynamic correlation than its predecessors.

show abstract

Section: Introductionmentioning

confidence: 99%

Electron Correlation in the Iron(II) Porphyrin by Natural Orbital Functional Approximations

Lew-Yee

Campo

Piris

2022

J. Chem. Theory Comput.

Self Cite

View full text Add to dashboard Cite

show abstract

“…These functionals are capable of achieving chemical accuracy in many cases; , however, they suffer from an important lack of dynamic correlation. To recover this correlation, orbital-invariant second-order perturbative corrections have been implemented , with significant results. , Note that an orbital-invariant formulation is used because the orbitals that serve as reference are the NOs resulting from an approximate NOF which are usually localized.…”

Section: Introductionmentioning

confidence: 99%

“…To recover this correlation, orbital-invariant second-order perturbative corrections have been implemented 53,54 with significant results. 55,56 Note that an orbital-invariant formulation is used because the orbitals that serve as reference are the NOs resulting from an approximate NOF which are usually localized.…”

Section: Introductionmentioning

confidence: 99%

Coupling Natural Orbital Functional Theory and Many-Body Perturbation Theory by Using Nondynamically Correlated Canonical Orbitals

Rodríguez‐Mayorga

Mitxelena

Bruneval

et al. 2021

J. Chem. Theory Comput.

Self Cite

View full text Add to dashboard Cite

We develop a new family of electronic structure methods for capturing at the same time the dynamic and nondynamic correlation effects. We combine the natural orbital functional theory (NOFT) and many-body perturbation theory (MBPT) through a canonicalization procedure applied to the natural orbitals to gain access to any MBPT approximation. We study three different scenarios: corrections based on second-order Møller−Plesset (MP2), random-phase approximation (RPA), and coupled-cluster singles doubles (CCSD). Several chemical problems involving different types of electron correlation in singlet and multiplet spin states have been considered. Our numerical tests reveal that RPA-based and CCSD-based corrections provide similar relative errors in molecular dissociation energies (D e ) to the results obtained using a MP2 correction. With respect to the MP2 case, the CCSD-based correction improves the prediction, while the RPA-based correction reduces the computational cost.

show abstract

“…Actually, the correction E dyn is based on an orbital-invariant formulation of the MP2 energy [31]. It has been observed that NOF-MP2 is able to give a quantitative agreement for dissociation energies, with a performance comparable to that of the accurate CASPT2 method in hydrogen abstraction reactions [32].…”

Section: Introductionmentioning

confidence: 99%

Chemical Reactivity Studies by the Natural-Orbital-Functional 2nd-Order-Moller-Plesset (NOF-MP2) method. Water Dehydrogenation by the Scandium Cation

Mercero¹,

Ugalde²,

Piris³

2020

Preprint

Self Cite

View full text Add to dashboard Cite

The reliability of the recently proposed natural orbital functional supplemented with second-order Møller-Plesset calculations, (NOF-MP2), has been assessed for the mechanistic studies of elementary reactions of transition metal compounds by investigating the dehydrogenation of water by the scandium cation. Both high-and low-spin state potential energy surfaces have been searched thoroughly. Special attention has been paid to the assessment of the capability of the NOF-MP2 method to describe the strong, both static and dynamic, electron correlation effects on the reactivity of Sc + ( 3 D, 1 D) with water. In agreement with experimental observations, our calculations correctly predict that the only exothermic products are the lowest-lying ScO + ( 1 Σ) and H2( 1 Σ + g ) species. Nevertheless, an in-depth analysis of the reaction paths leading to several additional products was carried out, including the characterization of various minima and several key transition states. Our results have been compared with the highly accurate multiconfigurational supplemented with quasi degenerate perturbation theory, MCQDPT, wavefunction-type calculations, and with the available experimental data. It is observed that NOF-MP2 is able to give a satisfactorily quantitative agreement, with a performance on par with that of the MCQDPT method.

show abstract

Performance of the NOF-MP2 method in hydrogen abstraction reactions

Cited by 11 publications

References 46 publications

Electron Correlation in the Iron(II) Porphyrin by Natural Orbital Functional Approximations

Electron Correlation in the Iron(II) Porphyrin by Natural Orbital Functional Approximations

Coupling Natural Orbital Functional Theory and Many-Body Perturbation Theory by Using Nondynamically Correlated Canonical Orbitals

Chemical Reactivity Studies by the Natural-Orbital-Functional 2nd-Order-Moller-Plesset (NOF-MP2) method. Water Dehydrogenation by the Scandium Cation

Contact Info

Product

Resources

About