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Claudio Amovilli - One of the best experts on this subject based on the ideXlab platform.
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Self-Consistent-Field Calculation of Pauli Repulsion and Dispersion Contributions to the Solvation Free Energy in the Polarizable Continuum Model
The Journal of Physical Chemistry B, 1997Co-Authors: Claudio Amovilli, Benedetta MennucciAbstract:By using the theory of intermolecular forces, two new expressions for Pauli repulsion and Dispersion Contributions to the solvation free energy are derived. These expressions contain explicitly the solute electron density and, therefore, can be used directly in the SCF calculation of the solute wave function within the polarizable continuum model (PCM). The final expressions are very simple and include also some intrinsic solvent properties which are, for repulsion, the density, the molecular weight, the number of valence electrons, and for Dispersion, the refractive index and the ionization potential. This new approach does not depend on any given intermolecular potential and it can be adapted to any choice of basis set. For small-size basis sets, even minimal, the Dispersion Contribution is obtained in two steps and includes the effect of adding diffuse and polarization functions, not used in the wave function itself. This method has been implemented in our HONDO package, in a version which includes the...
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Calculation of the Dispersion energy Contribution to the solvation free energy
Chemical Physics Letters, 1994Co-Authors: Claudio AmovilliAbstract:Abstract A general expression for the Dispersion energy Contribution to the solvation free energy is derived by exploiting the analogy between certain aspects of the theory of intermolecular forces and of the theory of solvation in the polarizable continuum model. The proposed method of calculation requires a knowledge of the solvent dielectric constant at imaginary frequencies, often efficiently approximated in terms of simple experimental data such as refractive index and ionization potential, and molecular transition densities and energies obtained by standard ab initio methods. By way of examples, the Dispersion Contribution is calculated for the systems CH 4 , NH 3 , H 2 O, HF and Ne in water as solvent.
Donald G Truhlar - One of the best experts on this subject based on the ideXlab platform.
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Uniform Treatment of Solute-Solvent Dispersion in the Ground and Excited Electronic States of the Solute Based on a Solvation Model with State-Specific Polarizability.
Journal of chemical theory and computation, 2013Co-Authors: Aleksandr V. Marenich, Christopher J. Cramer, Donald G TruhlarAbstract:We present a new kind of treatment of the solute-solvent Dispersion Contribution to the free energy of solvation using a solvation model with state-specific polarizability (SMSSP). To evaluate the solute-solvent Dispersion Contribution, the SMSSP model utilizes only two descriptors, namely, the spherically averaged dipole polarizability of the solute molecule (either in its ground or excited electronic state) and the refractive index of the solvent. The model was parametrized over 643 ground-state solvation free energy data for 231 solutes in 14 nonpolar, non-hydrogen-bonding solvents. We show that the SMSSP model is applicable to solutes in both the ground and the excited electronic state. For example, in comparison to available experimental data, the model yields qualitatively accurate predictions of the solvatochromic shifts for a number of systems where solute-solvent Dispersion is the dominant contributor to the shift.
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sorting out the relative Contributions of electrostatic polarization Dispersion and hydrogen bonding to solvatochromic shifts on vertical electronic excitation energies
Journal of Chemical Theory and Computation, 2010Co-Authors: Aleksandr V. Marenich, Christopher J. Cramer, Donald G TruhlarAbstract:Conventional polarized continuum model calculations of solvatochromic shifts on electronic excitation energies using popular quantum chemical programs (e.g., Gaussian or Turbomole) include the noninertial and inertial bulk-solvent polarization, which will be called electrostatics, but not Dispersion interactions and specific effects like hydrogen bonding. For the nf!* excitation of acetone in several solvents, we estimated the nonelectrostatic Contributions in two ways: (i) the vertical excitation model (VEM) of Li et al. (Int. J. Quantum Chem.2000,77, 264), but updated to use TD-DFT corrected linear response with SMD atomic radii, and (ii) in the case of acetone in water, ensemble averaging over supermolecule calculations with up to 12 explicit solvent molecules selected from a molecular dynamics trajectory, with the explicit solvent surrounded by a continuum solvent. The TD-DFT VEM calculations carried out with the M06 density functional for 23 solvents result in a Dispersion Contribution to the red of 261-356 cm -1 and a hydrogen-bonding Contribution to the blue of up to 289 cm -1 .
Aleksandr V. Marenich - One of the best experts on this subject based on the ideXlab platform.
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Uniform Treatment of Solute-Solvent Dispersion in the Ground and Excited Electronic States of the Solute Based on a Solvation Model with State-Specific Polarizability.
Journal of chemical theory and computation, 2013Co-Authors: Aleksandr V. Marenich, Christopher J. Cramer, Donald G TruhlarAbstract:We present a new kind of treatment of the solute-solvent Dispersion Contribution to the free energy of solvation using a solvation model with state-specific polarizability (SMSSP). To evaluate the solute-solvent Dispersion Contribution, the SMSSP model utilizes only two descriptors, namely, the spherically averaged dipole polarizability of the solute molecule (either in its ground or excited electronic state) and the refractive index of the solvent. The model was parametrized over 643 ground-state solvation free energy data for 231 solutes in 14 nonpolar, non-hydrogen-bonding solvents. We show that the SMSSP model is applicable to solutes in both the ground and the excited electronic state. For example, in comparison to available experimental data, the model yields qualitatively accurate predictions of the solvatochromic shifts for a number of systems where solute-solvent Dispersion is the dominant contributor to the shift.
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sorting out the relative Contributions of electrostatic polarization Dispersion and hydrogen bonding to solvatochromic shifts on vertical electronic excitation energies
Journal of Chemical Theory and Computation, 2010Co-Authors: Aleksandr V. Marenich, Christopher J. Cramer, Donald G TruhlarAbstract:Conventional polarized continuum model calculations of solvatochromic shifts on electronic excitation energies using popular quantum chemical programs (e.g., Gaussian or Turbomole) include the noninertial and inertial bulk-solvent polarization, which will be called electrostatics, but not Dispersion interactions and specific effects like hydrogen bonding. For the nf!* excitation of acetone in several solvents, we estimated the nonelectrostatic Contributions in two ways: (i) the vertical excitation model (VEM) of Li et al. (Int. J. Quantum Chem.2000,77, 264), but updated to use TD-DFT corrected linear response with SMD atomic radii, and (ii) in the case of acetone in water, ensemble averaging over supermolecule calculations with up to 12 explicit solvent molecules selected from a molecular dynamics trajectory, with the explicit solvent surrounded by a continuum solvent. The TD-DFT VEM calculations carried out with the M06 density functional for 23 solvents result in a Dispersion Contribution to the red of 261-356 cm -1 and a hydrogen-bonding Contribution to the blue of up to 289 cm -1 .
Alexandre Kudlinski - One of the best experts on this subject based on the ideXlab platform.
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Grayness-dependent emission of dispersive waves from dark solitons in optical fibers
Optics letters, 2018Co-Authors: T. Marest, C. Mas Arabí, Matteo Conforti, Arnaud Mussot, Carles Milián, Dmitry V. Skryabin, Alexandre KudlinskiAbstract:We report the experimental observation of dispersive wave emission from gray solitons propagating in the normal Dispersion region of an optical fiber. Besides observing for the first time, to the best of our knowledge, the emission of a dispersive wave from an isolated dark soliton, we show that the dispersive wave frequency and amplitude strongly depend on soliton grayness. This process can be explained by the higher-order Dispersion Contribution into the phase-matching condition and the grayness of the soliton. Numerical simulations and theoretical predictions are in good agreement with the experiments.
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Grayness-dependent emission of dispersive waves from dark solitons in optical fibers
Optics Letters, 2018Co-Authors: T. Marest, C. Mas Arabí, Matteo Conforti, Arnaud Mussot, Carles Milián, Dmitry V. Skryabin, Alexandre KudlinskiAbstract:We report the experimental observation of dispersive wave emission from gray solitons propagating in the normal Dispersion region of an optical fiber. Besides observing for the first time the emission of a disper-sive wave from an isolated dark soliton, we show that the dispersive wave frequency and amplitude strongly depends on soliton grayness. This process can be explained by the higher-order Dispersion Contribution into the phase-matching condition and the grayness of the soliton. Numerical simulations and theoretical predictions are in good agreement with the experiments.
Benedetta Mennucci - One of the best experts on this subject based on the ideXlab platform.
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Self-Consistent-Field Calculation of Pauli Repulsion and Dispersion Contributions to the Solvation Free Energy in the Polarizable Continuum Model
The Journal of Physical Chemistry B, 1997Co-Authors: Claudio Amovilli, Benedetta MennucciAbstract:By using the theory of intermolecular forces, two new expressions for Pauli repulsion and Dispersion Contributions to the solvation free energy are derived. These expressions contain explicitly the solute electron density and, therefore, can be used directly in the SCF calculation of the solute wave function within the polarizable continuum model (PCM). The final expressions are very simple and include also some intrinsic solvent properties which are, for repulsion, the density, the molecular weight, the number of valence electrons, and for Dispersion, the refractive index and the ionization potential. This new approach does not depend on any given intermolecular potential and it can be adapted to any choice of basis set. For small-size basis sets, even minimal, the Dispersion Contribution is obtained in two steps and includes the effect of adding diffuse and polarization functions, not used in the wave function itself. This method has been implemented in our HONDO package, in a version which includes the...