Explicit Polarization (X-Pol) Potential Using ab Initio Molecular Orbital Theory and Density Functional Theory

Song, Lingchun; Han, Jaebeom; Lin, Yen Lin; Xie, Wangshen; Gao, Jiali

doi:10.1021/jp902710a

Cited by 52 publications

(130 citation statements)

References 70 publications

Supporting

Mentioning

128

Contrasting

Order By: Relevance

“…29,31,32 One of the SCF procedures corresponds to molecular orbital optimizations for the individual fragments under the external electrostatic potential of the remaining fragments. In the nonvariational version of X-Pol that is used here, this electrostatic potential is the same as is used in quantum mechanical/molecular mechanical (QM/MM) calculations based on partial atomic charges.…”

Section: Computational Detailsmentioning

confidence: 99%

“…73) basis set because this basis set provides reasonable Mulliken charge distributions. 32 (However, one can also use more accurate charge models [74][75][76] in future work.) In the numerical calculation of the exchange-correlation energy, polar coordinates are employed for the grid generation.…”

Section: Computational Detailsmentioning

confidence: 99%

“…77,78 The present LJ parameters are taken from the previous X-Pol work 32 for C, O, and N atoms except that here we use an arithmetic mean in Eq. (19b), and Ref.…”

Section: Computational Detailsmentioning

confidence: 99%

“…The explicit polarization (X-Pol) method [29][30][31][32] is a model that describes polarization by a quantum mechanical treatment of molecular electron densities (as opposed to many other models that are essentially classical, such as molecular mechanics). In this model, a condensed-phase system is divided into interacting fragments, the internal energies of the fragments are treated with quantum mechanical electronic structure theory, and the interactions between fragments are described by electrostatistics and empirical functions for the description of exchange repulsion and dispersion-like interactions between fragments.…”

Section: Introductionmentioning

confidence: 99%

“…The true interfragment interaction may be decomposed into five components: electrostatic, polarization, exchange-repulsion, dispersion, and charge transfer interactions. In the X-Pol method, the electrostatic interaction can be described using a variety of approaches, including the approximation used here that the electrostatic potential of the other fragments is given by the Coulomb potential of partial atomic charges 29,31,32 (one can also use multipole moments 33 ). The exchange repulsion interactions can be estimated by antisymmetrizing the X-Pol wave function 34 using the block-localized wave function (BLW) approach.…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Incorporation of charge transfer into the explicit polarization fragment method by grand canonical density functional theory

Isegawa

Gao

Truhlar

2011

The Journal of Chemical Physics

Self Cite

View full text Add to dashboard Cite

Molecular fragmentation algorithms provide a powerful approach to extending electronic structure methods to very large systems. Here we present a method for including charge transfer between molecular fragments in the explicit polarization (X-Pol) fragment method for calculating potential energy surfaces. In the conventional X-Pol method, the total charge of each fragment is preserved, and charge transfer between fragments is not allowed. The description of charge transfer is made possible by treating each fragment as an open system with respect to the number of electrons. To achieve this, we applied Mermin's finite temperature method to the X-Pol wave function. In the application of this method to X-Pol, the fragments are open systems that partially equilibrate their number of electrons through a quasithermodynamics electron reservoir. The number of electrons in a given fragment can take a fractional value, and the electrons of each fragment obey the Fermi-Dirac distribution. The equilibrium state for the electrons is determined by electronegativity equalization with conservation of the total number of electrons. The amount of charge transfer is controlled by re-interpreting the temperature parameter in the Fermi-Dirac distribution function as a coupling strength parameter. We determined this coupling parameter so as to reproduce the charge transfer energy obtained by block localized energy decomposition analysis. We apply the new method to ten systems, and we show that it can yield reasonable approximations to potential energy profiles, to charge transfer stabilization energies, and to the direction and amount of charge transferred.

show abstract

Section: Computational Detailsmentioning

confidence: 99%

Section: Computational Detailsmentioning

confidence: 99%

“…77,78 The present LJ parameters are taken from the previous X-Pol work 32 for C, O, and N atoms except that here we use an arithmetic mean in Eq. (19b), and Ref.…”

Section: Computational Detailsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Incorporation of charge transfer into the explicit polarization fragment method by grand canonical density functional theory

Isegawa

Gao

Truhlar

2011

The Journal of Chemical Physics

Self Cite

View full text Add to dashboard Cite

show abstract

Polarizable Force Fields for Biomolecular Modeling

Shi¹,

Ren²,

Schnieders³

et al. 2015

Reviews in Computational Chemistry

110

View full text Add to dashboard Cite

Classical electrostatics models that take into account polarization appeared as early as the 1950s. Barker in his 1953 paper "Statistical Mechanics of Interacting Dipoles" discussed the electrostatic energy of molecules in terms of "permanent and induced dipoles". 13 Currently, polarizable models generally fall into three categories: those based on induced point dipoles, 9, 14-23 the classical Drude oscillators, 24-26 and fluctuating charges. 27-30 More sophisticated force fields that are "electronic structure-based" 31, 32 or use "machine learning methods" 33 also exist, but incur higher computational costs. Discussions of the advantages and disadvantages of each model and their applications will be presented in the following sections. Compared to fixed charge models, the polarizable models are still in a relatively early stage. Only in the past decade or so has there been a systematic effort to develop general polarizable force fields for molecular modeling. A number of reviews have been published to discuss various aspects of polarizable force fields and their development. 9, 34-40 Here, we focus on the recent development and applications of different polarizable force fields. We begin with a brief introduction to the basic principles and formulae underlying alternative models. Next, the recent progress of several well-developed polarizable force fields is reviewed. Finally, applications of polarizable models to a range of molecular systems, including water and other small molecules, ion solvation, peptides, proteins and lipid systems are presented.

show abstract

Dipole preserving and polarization consistent charges

2011

Self Cite

View full text Add to dashboard Cite

A method for estimating dipole preserving and polarization consistent (DPPC) charges is described, which reproduces exactly the molecular dipole moment as well as the local, atomic hybridization dipoles determined from the corresponding wave function, and can yield accurate molecular polarization. The method is based on a model described by Thole and van Duijnen and a new feature is introduced in the DPPC model to treat molecular polarization. Thus, the DPPC method offers a convenient procedure to describe molecular polarization in applications using semiempirical models and ab initio molecular orbital theory with relatively small basis functions such as 6-31+G(d,p) or without inclusion of electron correlation; these methods tend to underestimate molecular polarizability. The trends of the DPPC partial atomic charges are found to be in good accord with those of the CM2 model, a class IV charge analysis method that has been used in a variety of applications. The DPPC method is illustrated to mimic the correct molecular polarizability in a water dimer test case and in water-halide ion complexes using the explicit polarization (X-Pol) potential with the AM1 Hamiltonian.

show abstract

Explicit Polarization (X-Pol) Potential Using ab Initio Molecular Orbital Theory and Density Functional Theory

Cited by 52 publications

References 70 publications

Incorporation of charge transfer into the explicit polarization fragment method by grand canonical density functional theory

Incorporation of charge transfer into the explicit polarization fragment method by grand canonical density functional theory

Polarizable Force Fields for Biomolecular Modeling

Dipole preserving and polarization consistent charges

Contact Info

Product

Resources

About