Evaluation of bismuth-based dispersion energy donors – synthesis, structure and theoretical study of 2-biphenylbismuth(iii) derivatives

<div>The so-called D4 model is presented for the accurate computation of London dispersion interactions in density functional theory approximations (DFT-D4) and generally for atomistic modelling methods. In this successor to the DFT-D3 model, the atomic coordination-dependent dipole polarizabilities are scaled based on atomic partial charges which can be taken from various sources. For this purpose, a new charge-dependent parameter-economic scaling function is designed. Classical charges are obtained from an atomic electronegativity equilibration procedure for which efficient analytical derivatives with respect to nuclear positions are developed. A numerical Casimir-Polder integration of the atom-in-molecule dynamic polarizabilities then yields charge- and geometry-dependent dipole-dipole dispersion coefficients. Similar to the D3 model, the dynamic polarizabilities are pre-computed by time-dependent DFT and all elements up to radon (Z = 86) are covered. The two-body dispersion energy expression has the usual sum-over-atom-pairs form and includes dipole-dipole, as well as dipole-quadrupole interactions. For a benchmark set of 1225 molecular dipole-dipole dispersion coefficients, the D4 model achieves an unprecedented accuracy with a mean relative deviation of 3.9% compared to 4.7% for D3. In addition to the two-body part, three-body effects are described by an Axilrod-Teller-Muto term. A common many-body dispersion expansion was extensively tested and an energy correction based on D4 polarizabilities is found to be advantageous for larger systems. Becke-Johnson-type damping parameters for DFT-D4 are determined for more than 60 common density functionals. For various standard energy benchmark sets DFT-D4 slightly but consistently outperforms DFT-D3. Especially for metal containing systems, the introduced charge dependence of the dispersion coefficients improves thermochemical properties. We suggest (DFT-)D4 as a physically improved and more sophisticated dispersion model in place of DFT-D3 for DFT calculations as well as other low-cost approaches like force-fields or semi-empirical models.</div>

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London Dispersion Helps Refine Steric A-Values: Dispersion Energy Donor Scales

Journal of the American Chemical Society ◽

10.1021/jacs.1c09222 ◽

2021 ◽

Author(s):

Ephrath Solel ◽

Marcel Ruth ◽

Peter R. Schreiner

Keyword(s):

Dispersion Energy ◽

Energy Donor ◽

London Dispersion

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Impact of Van der Waals interactions on structural and nonlinear optical properties of azobenzene switches

10.26434/chemrxiv.14731428.v1 ◽

2021 ◽

Author(s):

carmelo Naim ◽

Frédéric Castet ◽

Eduard Matito

Keyword(s):

Density Functional ◽

Nonlinear Optical ◽

Van Der Waals Interactions ◽

Dispersion Interactions ◽

Geometrical Structures ◽

Hartree Fock ◽

Meta Position ◽

Good Account ◽

London Dispersion ◽

Azobenzene Derivatives

<div> <div> <div> <p>The geometrical structures, relative Z-E energies, and second-order nonlinear responses of a collection of azobenzene molecules symmetrically substituted in meta- position with functional groups of different bulkiness are investigated using various ab initio and DFT levels of approximation. We show that RI-MP2 and RI-CC2 approximations provide very similar geometries and relative energies and evidence that London dispersion interactions existing between bulky meta-substituents stabilize the Z con- former. The !B97-X-D exchange-correlation functional provides an accurate description of these effects and gives a good account of the nonlinear optical response of the molecules. We show that density functional approximations should include no less than 50% of Hartree-Fock exchange to provide accurate hyperpolarizabilities. A property-structure analysis of the azobenzene derivatives reveals that the main contribution to the first hyperpolarizability comes from the azo bond, but phenyl meso-substituents can enhance it.</p> </div> </div> </div>

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Optical Properties and van der Waals-London Dispersion Interactions in Inorganic and Biomolecular Assemblies

MRS Proceedings ◽

10.1557/opl.2014.301 ◽

2014 ◽

Vol 1619 ◽

Author(s):

Daniel M. Dryden ◽

Yingfang Ma ◽

Jacob Schimelman ◽

Diana Acosta ◽

Lijia Liu ◽

...

Keyword(s):

Optical Properties ◽

Spectroscopic Ellipsometry ◽

Density Functional ◽

Type I Collagen ◽

Strong Dependence ◽

Van Der Waals ◽

Fundamental Absorption Edge ◽

Type I ◽

Dispersion Interactions ◽

London Dispersion

ABSTRACTThe optical properties and electronic structure of AlPO4, SiO2, Type I collagen, and DNA were examined to gain insight into the van der Waals-London dispersion behavior of these materials. Interband optical properties of AlPO4 and SiO2 were derived from vacuum ultraviolet spectroscopy and spectroscopic ellipsometry, and showed a strong dependence on the crystals’ constituent tetrahedral units, with strong implications for the role of phosphate groups in biological materials. The UV-Vis decadic molar absorption of four DNA oligonucleotides was measured, and showed a strong dependence on composition and stacking sequence. A film of Type I collagen was studied using spectroscopic ellipsometry, and showed a characteristic shoulder in the fundamental absorption edge at 6.05 eV. Ab initio calculations based on density functional theory corroborated the experimental results and provided further insights into the electronic structures, interband transitions and vdW-Ld interaction potentials for these materials.

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Dispersion Size-Consistency

Electronic Structure ◽

10.1088/2516-1075/ac495b ◽

2022 ◽

Author(s):

Brian Nguyen ◽

Devin J. Hernandez ◽

Emmanuel Victor V. Flores ◽

Filipp Furche

Keyword(s):

Random Phase ◽

System Size ◽

State Density ◽

Structure Theory ◽

Dispersion Interactions ◽

Dispersion Energy ◽

Supramolecular Materials ◽

Size Consistency ◽

Additive Separability ◽

Screening Factor

Abstract A multivariate adiabatic connection (MAC) framework for describing dispersion interactions in a system consisting of non-overlapping monomers is presented. By constraining the density to the physical ground-state density of the supersystem, the MAC enables a rigorous separation of induction and dispersion effects. The exact dispersion energy is obtained from the zero-temperature fluctuation-dissipation theorem and partitioned into increments corresponding to the interaction energy gained when an additional monomer is added to a -monomer system. The total dispersion energy of an -monomer system is independent of any partitioning into subsystems. This statement of dispersion size consistency is shown to be an exact constraint. The resulting additive separability of the dispersion energy results from multiplicative separability of the generalized screening factor defined as the inverse generalized dielectric function. Many-body perturbation theory (MBPT) is found to violate dispersion size-consistency because perturbative approximations to the generalized screening factor are nonseparable; on the other hand, random phase approximation-type methods produce separable generalized screening factors and therefore preserve dispersion size-consistency. This result further explains the previously observed increase in relative errors of MBPT for dispersion interactions as the system size increases. Implications for electronic structure theory and applications to supramolecular materials and condensed matter are discussed.

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Calculation of dispersion interactions with the geminal-based ring Coupled Cluster Doubles method

Theoretical Chemistry Accounts ◽

10.1007/s00214-020-02657-1 ◽

2020 ◽

Vol 139 (9) ◽

Author(s):

Á. Margócsy ◽

Á. Szabados

Keyword(s):

Wave Function ◽

Asymptotic Behaviour ◽

Noble Gas ◽

Valence Bond ◽

Coupled Cluster ◽

Leading Order ◽

Dispersion Interactions ◽

Dispersion Energy ◽

Generalized Valence Bond ◽

Noble Gas Dimers

Abstract The performance of the recently developed multi-reference extension of ring coupled cluster doubles is investigated for dispersion energy calculations, applied to the generalized valence bond wave function. The leading-order contribution to the dispersion energy is shown to have the correct asymptotic behaviour. Illustrative calculations on noble gas dimers are presented.

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Deuterium isotope effects in liquid-liquid phase diagrams: Water + phenol and water + 2-methylpropanoic acid systems

Australian Journal of Chemistry ◽

10.1071/ch9830215 ◽

1983 ◽

Vol 36 (2) ◽

pp. 215 ◽

Cited By ~ 4

Author(s):

DV Fenby ◽

JR Khurma ◽

ZS Kooner ◽

RF Smith

Keyword(s):

Liquid Phase ◽

Phase Diagrams ◽

Isotope Effects ◽

Dispersion Interactions ◽

Exchange Reactions ◽

Molar Excess ◽

Deuterium Isotope Effects ◽

London Dispersion ◽

Molar Excess Volumes ◽

System Water

Phase-separation temperatures Tp have been measured for the systems H2O+C6H5OH, H2O+ C6H5OD, H20+ CsD5OD, D20+ C6H50H, D2O+ C6H5OD, D2O+ C6DsOD, H2O+ (CH3)2CHCO2H and D2O+ (CH3)2CHCO2H. For water+ 2-methylpropanoic acid, the differences in the Tp-x curves for the exchange and no-exchange systems are striking. For water + phenol, on the other hand, the effect of deuterium-exchange reactions on the Tp-x curves is very small. The results for all systems are in accord with the qualitative predictions of the Rabinovich theory, which accounts for deuterium isotope effects in liquid-liquid phase diagrams in terms of hydrogen bond and London dispersion interactions. Molar excess enthalpies and molar excess volumes at 300.15 K are reported for the system water + 2-methylpropanoic acid. The results are compared with those for water + acetic acid.

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Optical Properties and van der Waals - London Dispersion Interactions of Polystyrene Determined by Vacuum Ultraviolet Spectroscopy and Spectroscopic Ellipsometry

Australian Journal of Chemistry ◽

10.1071/ch06222 ◽

2007 ◽

Vol 60 (4) ◽

pp. 251 ◽

Cited By ~ 42

Author(s):

Roger H. French ◽

Karen I. Winey ◽

Min K. Yang ◽

Weiming Qiu

Keyword(s):

Free Energy ◽

Optical Properties ◽

Surface Free Energy ◽

Vacuum Ultraviolet ◽

Van Der Waals ◽

Interband Transitions ◽

Dispersion Interactions ◽

Dispersion Component ◽

London Dispersion ◽

Hamaker Constants

The interband optical properties of polystyrene in the vacuum ultraviolet (VUV) region have been investigated using combined spectroscopic ellipsometry and VUV spectroscopy. Over the range 1.5–32 eV, the optical properties exhibit electronic transitions we assign to three groupings, E1, E2, and E3, corresponding to a hierarchy of interband transitions of aromatic (π → π*), non-bonding (n → π*, n → σ*), and saturated (σ → σ*) orbitals. In polystyrene there are strong features in the interband transitions arising from the side-chain π bonding of the aromatic ring consisting of a shoulder at 5.8 eV (E1′) and a peak at 6.3 eV (E1), and from the σ bonding of the C–C backbone at 12 eV (E3′) and 17.1 eV (E3). These E3 transitions have characteristic critical point line shapes associated with one-dimensionally delocalized electron states in the polymer backbone. A small shoulder at 9.9 eV (E2) is associated with excitations possibly from residual monomer or impurities. Knowledge of the valence electronic excitations of a material provides the necessary optical properties to calculate the van der Waals–London dispersion interactions using Lifshitz quantum electrodynamics theory and full spectral optical properties. Hamaker constants and the van der Waals–London dispersion component of the surface free energy for polystyrene were determined. These Lifshitz results were compared to the total surface free energy of polystyrene, polarity, and dispersive component of the surface free energy as determined from contact angle measurements with two liquids, and with literature values. The Lifshitz approach, using full spectral Hamaker constants, is a more direct determination of the van der Waals–London dispersion component of the surface free energy of polystyrene than other methods.

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