Publication

Reduced Common Molecular Orbital Basis for Nonorthogonal Configuration Interaction

Kathir, R. K., de Graaf, C., Broer, R. & Havenith, R. W. A., 12-May-2020, In : Journal of Chemical Theory and Computation. 16, 5, p. 2941-2951 11 p.

Research output: Contribution to journalArticleAcademicpeer-review

APA

Kathir, R. K., de Graaf, C., Broer, R., & Havenith, R. W. A. (2020). Reduced Common Molecular Orbital Basis for Nonorthogonal Configuration Interaction. Journal of Chemical Theory and Computation, 16(5), 2941-2951. https://doi.org/10.1021/acs.jctc.9b01144

Author

Kathir, R. K. ; de Graaf, Coen ; Broer, Ria ; Havenith, Remco W. A. / Reduced Common Molecular Orbital Basis for Nonorthogonal Configuration Interaction. In: Journal of Chemical Theory and Computation. 2020 ; Vol. 16, No. 5. pp. 2941-2951.

Harvard

Kathir, RK, de Graaf, C, Broer, R & Havenith, RWA 2020, 'Reduced Common Molecular Orbital Basis for Nonorthogonal Configuration Interaction', Journal of Chemical Theory and Computation, vol. 16, no. 5, pp. 2941-2951. https://doi.org/10.1021/acs.jctc.9b01144

Standard

Reduced Common Molecular Orbital Basis for Nonorthogonal Configuration Interaction. / Kathir, R. K.; de Graaf, Coen; Broer, Ria; Havenith, Remco W. A.

In: Journal of Chemical Theory and Computation, Vol. 16, No. 5, 12.05.2020, p. 2941-2951.

Research output: Contribution to journalArticleAcademicpeer-review

Vancouver

Kathir RK, de Graaf C, Broer R, Havenith RWA. Reduced Common Molecular Orbital Basis for Nonorthogonal Configuration Interaction. Journal of Chemical Theory and Computation. 2020 May 12;16(5):2941-2951. https://doi.org/10.1021/acs.jctc.9b01144


BibTeX

@article{9d7f098d725d4d5c97c1f870f443c2f3,
title = "Reduced Common Molecular Orbital Basis for Nonorthogonal Configuration Interaction",
abstract = "Electron and charge transfers are part of many vital processes in nature and technology. Ab initio descriptions of these processes provide useful insights that can be utilized for applications. A combination of the embedded cluster material model and nonorthogonal configuration interaction (NOCI), in which the cluster wave functions are expanded in many-electron basis functions (MEBFs) consisting of spin-adapted, antisymmetrized products of multiconfigurational wave functions of fragments (which are usually molecules) in the cluster, appears to provide a compromise between accuracy and calculation time. Additional advantages of this NOCI-Fragments approach are the chemically convenient interpretation of the wave function in terms of molecular states, and the direct accessibility of electronic coupling between diabatic states to describe energy and electron transfer processes. Bottlenecks in this method are the large number of two-electron integrals that have to be handled for the calculation of an electronic coupling matrix element and the enormous number of matrix elements over determinant pairs that have to be evaluated for the calculation of one matrix element between the MEBFs. We show here how we created a reduced common molecular orbital basis that is utilized to significantly reduce the number of two-electron integrals that need to be handled. The results obtained with this basis do not show any loss of accuracy in relevant quantities like electronic couplings and vertical excitation energies. We also show a significant reduction in computation time without loss in accuracy when matrix elements over determinant pairs with small weights are neglected in the NOCI. These improvements in the methodology render NOCI-Fragments to be also applicable to treat clusters of larger molecular systems with larger atomic basis sets and larger active spaces, as the computation time becomes dependent on the number of occupied orbitals and less dependent on the size of the active space.",
keywords = "VALENCE-BOND THEORY, HARTREE-FOCK THEORY, SINGLET FISSION, CHARGE-TRANSFER, MATRIX-ELEMENTS, HOLE STATES, ELECTRONIC-STRUCTURE, EXCITON, PENTACENE, TRANSPORT",
author = "Kathir, {R. K.} and {de Graaf}, Coen and Ria Broer and Havenith, {Remco W. A.}",
year = "2020",
month = "5",
day = "12",
doi = "10.1021/acs.jctc.9b01144",
language = "English",
volume = "16",
pages = "2941--2951",
journal = "Journal of Chemical Theory and Computation",
issn = "1549-9618",
publisher = "AMER CHEMICAL SOC",
number = "5",

}

RIS

TY - JOUR

T1 - Reduced Common Molecular Orbital Basis for Nonorthogonal Configuration Interaction

AU - Kathir, R. K.

AU - de Graaf, Coen

AU - Broer, Ria

AU - Havenith, Remco W. A.

PY - 2020/5/12

Y1 - 2020/5/12

N2 - Electron and charge transfers are part of many vital processes in nature and technology. Ab initio descriptions of these processes provide useful insights that can be utilized for applications. A combination of the embedded cluster material model and nonorthogonal configuration interaction (NOCI), in which the cluster wave functions are expanded in many-electron basis functions (MEBFs) consisting of spin-adapted, antisymmetrized products of multiconfigurational wave functions of fragments (which are usually molecules) in the cluster, appears to provide a compromise between accuracy and calculation time. Additional advantages of this NOCI-Fragments approach are the chemically convenient interpretation of the wave function in terms of molecular states, and the direct accessibility of electronic coupling between diabatic states to describe energy and electron transfer processes. Bottlenecks in this method are the large number of two-electron integrals that have to be handled for the calculation of an electronic coupling matrix element and the enormous number of matrix elements over determinant pairs that have to be evaluated for the calculation of one matrix element between the MEBFs. We show here how we created a reduced common molecular orbital basis that is utilized to significantly reduce the number of two-electron integrals that need to be handled. The results obtained with this basis do not show any loss of accuracy in relevant quantities like electronic couplings and vertical excitation energies. We also show a significant reduction in computation time without loss in accuracy when matrix elements over determinant pairs with small weights are neglected in the NOCI. These improvements in the methodology render NOCI-Fragments to be also applicable to treat clusters of larger molecular systems with larger atomic basis sets and larger active spaces, as the computation time becomes dependent on the number of occupied orbitals and less dependent on the size of the active space.

AB - Electron and charge transfers are part of many vital processes in nature and technology. Ab initio descriptions of these processes provide useful insights that can be utilized for applications. A combination of the embedded cluster material model and nonorthogonal configuration interaction (NOCI), in which the cluster wave functions are expanded in many-electron basis functions (MEBFs) consisting of spin-adapted, antisymmetrized products of multiconfigurational wave functions of fragments (which are usually molecules) in the cluster, appears to provide a compromise between accuracy and calculation time. Additional advantages of this NOCI-Fragments approach are the chemically convenient interpretation of the wave function in terms of molecular states, and the direct accessibility of electronic coupling between diabatic states to describe energy and electron transfer processes. Bottlenecks in this method are the large number of two-electron integrals that have to be handled for the calculation of an electronic coupling matrix element and the enormous number of matrix elements over determinant pairs that have to be evaluated for the calculation of one matrix element between the MEBFs. We show here how we created a reduced common molecular orbital basis that is utilized to significantly reduce the number of two-electron integrals that need to be handled. The results obtained with this basis do not show any loss of accuracy in relevant quantities like electronic couplings and vertical excitation energies. We also show a significant reduction in computation time without loss in accuracy when matrix elements over determinant pairs with small weights are neglected in the NOCI. These improvements in the methodology render NOCI-Fragments to be also applicable to treat clusters of larger molecular systems with larger atomic basis sets and larger active spaces, as the computation time becomes dependent on the number of occupied orbitals and less dependent on the size of the active space.

KW - VALENCE-BOND THEORY

KW - HARTREE-FOCK THEORY

KW - SINGLET FISSION

KW - CHARGE-TRANSFER

KW - MATRIX-ELEMENTS

KW - HOLE STATES

KW - ELECTRONIC-STRUCTURE

KW - EXCITON

KW - PENTACENE

KW - TRANSPORT

U2 - 10.1021/acs.jctc.9b01144

DO - 10.1021/acs.jctc.9b01144

M3 - Article

VL - 16

SP - 2941

EP - 2951

JO - Journal of Chemical Theory and Computation

JF - Journal of Chemical Theory and Computation

SN - 1549-9618

IS - 5

ER -

ID: 126999290