X

Search Results

Searching....

12.1 Introduction

12.1.1 Overview

(December 20, 2021)

Molecular complexes and molecular clusters represent a broad class of systems with interesting chemical and physical properties. Such systems can be naturally partitioned into fragments each representing a molecule or several molecules. Q-Chem contains a set of methods designed to use such partitioning either for physical or computational advantage. Some of these methods (e.g. the ALMO-EDA method and its most recent updates/extensions) were developed and implemented by Dr. Rustam Z. Khaliullin, Dr. Paul R. Horn, Dr. Yuezhi Mao, Dr. Jonathan Thirman, Dr. Daniel S. Levine, Dr. Qinghui Ge, and Matthias Loipersberger working with Prof. Martin Head-Gordon at the University of California–Berkeley. Other methods [e.g., the XSAPT family of methods and TDDFT(MI)] were developed by Drs. Leif Jacobson, Ka Un Lao, and Jie Liu working with Prof. John Herbert at Ohio State University.

The list of methods that use partitioning includes:

  • Initial guess at the MOs as a superposition of the converged MOs on the isolated fragments (FRAGMO guess). 564 Khaliullin R. Z., Head-Gordon M., Bell A. T.
    J. Chem. Phys.
    (2006), 124, pp. 204105.
    Link

  • Constrained (locally-projected) SCF methods for molecular interactions (SCF MI methods) between both closed-shell 564 Khaliullin R. Z., Head-Gordon M., Bell A. T.
    J. Chem. Phys.
    (2006), 124, pp. 204105.
    Link
    and open-shell 487 Horn P. R. et al.
    J. Chem. Phys.
    (2013), 138, pp. 134119.
    Link
    fragments.

  • Single Roothaan-step (RS) correction methods that improve FRAGMO and SCF MI description of molecular systems. 564 Khaliullin R. Z., Head-Gordon M., Bell A. T.
    J. Chem. Phys.
    (2006), 124, pp. 204105.
    Link
    , 487 Horn P. R. et al.
    J. Chem. Phys.
    (2013), 138, pp. 134119.
    Link

  • Automated calculation of the BSSE with counterpoise correction method (full SCF and RS implementation).

  • The original version the ALMO-EDA method (energy decomposition analysis based on absolutely localized molecular orbitals), including the associated charge transfer analysis, 563 Khaliullin R. Z. et al.
    J. Phys. Chem. A
    (2007), 111, pp. 8753.
    Link
    , 561 Khaliullin R. Z., Bell A. T., Head-Gordon M.
    J. Chem. Phys.
    (2008), 128, pp. 184112.
    Link
    , 487 Horn P. R. et al.
    J. Chem. Phys.
    (2013), 138, pp. 134119.
    Link
    and the analysis of intermolecular bonding in terms of complementary occupied-virtual pairs (COVPs). 561 Khaliullin R. Z., Bell A. T., Head-Gordon M.
    J. Chem. Phys.
    (2008), 128, pp. 184112.
    Link
    , 562 Khaliullin R. Z., Bell A. T., Head-Gordon M.
    Chem. Eur. J
    (2009), 15, pp. 851.
    Link
    , 487 Horn P. R. et al.
    J. Chem. Phys.
    (2013), 138, pp. 134119.
    Link

  • The second-generation ALMO-EDA method, 486 Horn P. R., Mao Y., Head-Gordon M.
    Phys. Chem. Chem. Phys.
    (2016), 18, pp. 23067.
    Link
    , 738 Mao Y. et al.
    Annu. Rev. Phys. Chem.
    (2021), 72, pp. 641.
    Link
    , 483 Horn P. R., Head-Gordon M.
    J. Chem. Phys.
    (2015), 143, pp. 114111.
    Link
    , 485 Horn P. R., Mao Y., Head-Gordon M.
    J. Chem. Phys.
    (2016), 144, pp. 114107.
    Link
    , 737 Mao Y. et al.
    Phys. Chem. Chem. Phys.
    (2020), 22, pp. 12867.
    Link
    including its extension to single-bond interactions 676 Levine D. S. et al.
    J. Chem. Theory Comput.
    (2016), 12, pp. 4812.
    Link
    , 674 Levine D. S., Head-Gordon M.
    J. Phys. Chem. Lett.
    (2017), 8, pp. 1967.
    Link
    , 675 Levine D. S., Head-Gordon M.
    Proc. Natl. Acad. Sci. USA
    (2017), 114, pp. 12649.
    Link
    and the ALMO-EDA(solv) scheme 739 Mao Y. et al.
    Chem. Sci.
    (2021), 12, pp. 1398.
    Link
    for the inclusion of implicit solvents in EDA calculation.

  • The adiabatic ALMO-EDA method that analyzes the effects intermolecular interactions on molecular properties. 736 Mao Y., Horn P. R., Head-Gordon M.
    Phys. Chem. Chem. Phys.
    (2017), 19, pp. 5944.
    Link
    , 716 Loipersberger M., Mao Y., Head-Gordon M.
    J. Chem. Theory Comput.
    (2020), 16, pp. 1073.
    Link

  • An extension of the ALMO-EDA to RI-MP2. 1117 Thirman J., Head-Gordon M.
    J. Chem. Phys.
    (2015), 143, pp. 084124.
    Link
    , 1118 Thirman J., Head-Gordon M.
    J. Phys. Chem. A
    (2017), 121, pp. 717.
    Link
    , 715 Loipersberger M. et al.
    J. Phys. Chem. A
    (2019), 123, pp. 9621.
    Link

  • An extension of the ALMO-EDA to intermolecular interactions involving excited-state molecules (calculated by CIS or TDDFT/TDA). 354 Ge Q., Mao Y., Head-Gordon M.
    J. Chem. Phys.
    (2018), 148, pp. 064105.
    Link
    , 353 Ge Q., Head-Gordon M.
    J. Chem. Theory Comput.
    (2018), 14, pp. 5156.
    Link

  • The variational explicit polarization (XPol) method, a self-consistent, charge-embedded, monomer-based SCF calculation. 1246 Xie W. et al.
    J. Chem. Phys.
    (2008), 128, pp. 234108.
    Link
    , 511 Jacobson L. D., Herbert J. M.
    J. Chem. Phys.
    (2011), 134, pp. 094118.
    Link
    , 456 Herbert J. M. et al.
    Phys. Chem. Chem. Phys.
    (2012), 14, pp. 7679.
    Link

  • Symmetry-adapted perturbation theory (SAPT), a monomer-based method for computing intermolecular interaction energies and decomposing them into physically-meaningful components. 524 Jeziorski B., Moszynski R., Szalewicz K.
    Chem. Rev.
    (1994), 94, pp. 1887.
    Link
    , 1105 Szalewicz K.
    Wiley Interdiscip. Rev.: Comput. Mol. Sci.
    (2012), 2, pp. 254.
    Link

  • XPol+SAPT (XSAPT), which extends the SAPT methodology to systems consisting of more than two monomers. 511 Jacobson L. D., Herbert J. M.
    J. Chem. Phys.
    (2011), 134, pp. 094118.
    Link
    , 456 Herbert J. M. et al.
    Phys. Chem. Chem. Phys.
    (2012), 14, pp. 7679.
    Link
    , 512 Jacobson L. D. et al.
    Annu. Rep. Comp. Chem.
    (2013), 9, pp. 25.
    Link

  • Closed- and open-shell AO-XSAPT(KS)+D, a dispersion-corrected version of XSAPT in atomic orbital basis that affords accurate intermolecular interaction energies at very low cost. 630 Lao K. U., Herbert J. M.
    J. Phys. Chem. Lett.
    (2012), 3, pp. 3241.
    Link
    , 631 Lao K. U., Herbert J. M.
    J. Chem. Phys.
    (2013), 139, pp. 034107.
    Link
    , 633 Lao K. U., Herbert J. M.
    J. Phys. Chem. A
    (2015), 119, pp. 235.
    Link

  • A stable and physically-motivated energy decomposition approach, SAPT/cDFT, in which cDFT is used to define the charge-transfer component of the interaction energy and SAPT defines the electrostatic, polarization, Pauli repulsion, and van der Waals contributions. 634 Lao K. U., Herbert J. M.
    J. Chem. Theory Comput.
    (2016), 12, pp. 2569.
    Link

  • The electrostatically-embedded many-body expansion 246 Dahlke E. E., Truhlar D. G.
    J. Chem. Theory Comput.
    (2007), 3, pp. 46.
    Link
    , 969 Richard R. M., Lao K. U., Herbert J. M.
    J. Chem. Phys.
    (2014), 141, pp. 014108.
    Link
    , 970 Richard R. M., Lao K. U., Herbert J. M.
    Acc. Chem. Res.
    (2014), 47, pp. 2828.
    Link
    , 637 Lao K. U. et al.
    J. Chem. Phys.
    (2016), 144, pp. 164105.
    Link
    and the fragment molecular orbital method, 570 Kitaura K. et al.
    Chem. Phys. Lett.
    (1999), 313, pp. 701.
    Link
    for decomposing large clusters into small numbers of monomers, facilitating larger calculations.

  • The Ab Initio Frenkel Davydov Model, 796 Morrison A. F., You Z.-Q., Herbert J. M.
    J. Chem. Theory Comput.
    (2014), 10, pp. 5366.
    Link
    , 793 Morrison A. F., Herbert J. M.
    J. Phys. Chem. Lett.
    (2015), 6, pp. 4390.
    Link
    a low-order scaling, highly parallelizable approach to computing excited state properties of liquids, crystals, and aggregates.

  • TDDFT for molecular interactions [TDDFT(MI)], an excited-state extension of SCF MI that offers a reduced-cost way to compute excited states in molecular clusters, crystals, and aggregates. 700 Liu J., Herbert J. M.
    J. Chem. Phys.
    (2015), 143, pp. 034106.
    Link
    , 701 Liu J., Herbert J. M.
    J. Chem. Theory Comput.
    (2016), 12, pp. 157.
    Link
    , 459 Herbert J. M. et al.
    Acc. Chem. Res.
    (2016), 49, pp. 931.
    Link

  • The ALMO-CIS and ALMO-CIS+CT models (also applicable to TDDFT/TDA) for computing a substantial number of excited states in large molecular clusters. 212 Closser K. D. et al.
    J. Chem. Theory Comput.
    (2015), 11, pp. 5791.
    Link
    , 355 Ge Q. et al.
    J. Chem. Phys.
    (2017), 146, pp. 044111.
    Link

Other fragment-based approaches in Q-Chem include:

  • The Effective Fragment Potential (EFP) method 357 Ghosh D. et al.
    J. Phys. Chem. A
    (2010), 114, pp. 12739.
    Link
    developed by Prof. Lyudmila Slipchenko at Purdue University and Prof. Anna Krylov at USC (see Section 11.5)

  • Fragment-based approaches to diabatic states and electronic couplings (see Section 10.14.3)