Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

¹H NMR: Interpreting Distorted and Overlapping Signals01:02

¹H NMR: Interpreting Distorted and Overlapping Signals

1.1K
Spin systems where the difference in chemical shifts of the coupled nuclei is greater than ten times J are called first-order spin systems. These nuclei are weakly coupled, and their chemical shifts and coupling constant can generally be estimated from the well-separated signals in the spectrum.
As Δν decreases and the signals move closer, the doublets appear increasingly distorted. The intensities of the inner lines increase at the cost of those of the outer lines as the signals are...
1.1K
Woodward–Hoffmann Selection Rules and Microscopic Reversibility01:34

Woodward–Hoffmann Selection Rules and Microscopic Reversibility

3.3K
Electrocyclic reactions, cycloadditions, and sigmatropic rearrangements are concerted pericyclic reactions that proceed via a cyclic transition state. These reactions are stereospecific and regioselective. The stereochemistry of the products depends on the symmetry characteristics of the interacting orbitals and the reaction conditions. Accordingly, pericyclic reactions are classified as either symmetry-allowed or symmetry-forbidden. Woodward and Hoffmann presented the selection criteria for...
3.3K
Second Order systems II01:18

Second Order systems II

171
In an underdamped second-order system, where the damping ratio ζ is between 0 and 1, a unit-step input results in a transfer function that, when transformed using the inverse Laplace method, reveals the output response. The output exhibits a damped sinusoidal oscillation, and the difference between the input and output is termed the error signal. This error signal also demonstrates damped oscillatory behavior. Eventually, as the system reaches a steady state, the error diminishes to zero.
171
Second Order systems I01:20

Second Order systems I

233
A servo system exemplifies a second-order system, featuring a proportional controller and load elements that ensure the output position aligns with the input position. The relationship between these components is described by a second-order differential equation. Applying the Laplace transform under zero initial conditions yields the transfer function, showing how inputs are converted to outputs in the system.
By reinterpreting the system, one can derive the closed-loop transfer function, which...
233
Double Resonance Techniques: Overview01:12

Double Resonance Techniques: Overview

291
Double resonance techniques in Nuclear Magnetic Resonance (NMR) spectroscopy involve the simultaneous application of two different frequencies or radiofrequency pulses to manipulate and observe two distinct nuclear spins. One important application of double resonance is spin decoupling, which selectively suppresses coupling with one type of nucleus while observing the NMR signal from another nucleus, simplifying the spectrum and enhancing resolution.
Spin decoupling is usually achieved by...
291
Chemical Shift: Internal References and Solvent Effects01:17

Chemical Shift: Internal References and Solvent Effects

764
In an NMR sample, precise measurement of the absolute absorption frequencies of nuclei is difficult. A standard internal reference compound is added, and the frequency difference between the reference signal and sample signals is measured.
The internal reference compound generally used in NMR spectroscopy is tetramethylsilane (TMS). TMS is preferred because it is chemically inert, soluble in NMR solvents, and easily removable. Also, the highly shielded methyl protons in TMS yield an intense...
764

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Why projection-based WF-in-DFT cannot be exact, even with the exact exchange-correlation functional. Formal and practical sources of errors.

The Journal of chemical physics·2026
Same author

Optimally Tuned Multiconfigurational Short-Range DFT for Linear Response Properties.

The journal of physical chemistry. A·2026
Same author

Projection-Based DMRG-in-DFT Embedding Corrected by Nonadditive Exchange-Correlation.

Journal of chemical theory and computation·2026
Same author

Time-Dependent Multiconfigurational Short-Range Density Functional Theory with Generalized Valence Bond Wave Functions.

The journal of physical chemistry. A·2025
Same author

Correcting Basis Set Incompleteness in Wave Function Correlation Energy by Dressing Electronic Hamiltonian with an Effective Short-Range Interaction.

The journal of physical chemistry letters·2025
Same author

Estimating the Complete Basis Set Extrapolation Error through Random Walks.

The journal of physical chemistry letters·2025
Same journal

Nuclear Gradients from Auxiliary-Field Quantum Monte Carlo and Their Applications in ML-Driven Geometry Optimization and Transition State Search.

Journal of chemical theory and computation·2026
Same journal

Correction to "Cluster-in-Molecule Local Correlation Method with an Accurate Distant Pair Correction for Large Systems".

Journal of chemical theory and computation·2026
Same journal

Machine-Learned Force Fields for Lattice Dynamics at Coupled-Cluster Level Accuracy.

Journal of chemical theory and computation·2026
Same journal

Systematic Molecularity-Dependent Entropy Errors in Continuum/RRHO Solution Thermochemistry: Origin and Correction.

Journal of chemical theory and computation·2026
Same journal

After 100 Years of Quantum Mechanics: Toward a Constructive Observation-Centered Perspective.

Journal of chemical theory and computation·2026
Same journal

Sample-Based Quantum Diagonalization Methods for Modeling the Photochemistry of Diazirine and Diazo Compounds.

Journal of chemical theory and computation·2026
See all related articles

Related Experiment Video

Updated: Sep 10, 2025

Excitonic Hamiltonians for Calculating Optical Absorption Spectra and Optoelectronic Properties of Molecular Aggregates and Solids
08:04

Excitonic Hamiltonians for Calculating Optical Absorption Spectra and Optoelectronic Properties of Molecular Aggregates and Solids

Published on: May 27, 2020

8.5K

First-Order Symmetry-Adapted Perturbation Theory with Double Exchange for Multireference Systems.

Dominik Cieśliński1, Michał Przybytek1, Grzegorz Chałasiński1

  • 1University of Warsaw, Faculty of Chemistry, ul. L. Pasteura 1, 02-093 Warsaw, Poland.

Journal of Chemical Theory and Computation
|August 20, 2025
PubMed
Summary
This summary is machine-generated.

This study enhances multiconfigurational symmetry-adapted perturbation theory (SAPT(MC)) to include double-exchange effects for improved interaction energy calculations. The new methods are tested on model systems, offering better accuracy for molecular interactions.

More Related Videos

Isotopic Effect in Double Proton Transfer Process of Porphycene Investigated by Enhanced QM/MM Method
05:51

Isotopic Effect in Double Proton Transfer Process of Porphycene Investigated by Enhanced QM/MM Method

Published on: July 19, 2019

6.3K
Practical Aspects of Sample Preparation and Setup of 1H R1ρ Relaxation Dispersion Experiments of RNA
08:17

Practical Aspects of Sample Preparation and Setup of 1H R1ρ Relaxation Dispersion Experiments of RNA

Published on: July 9, 2021

4.8K

Related Experiment Videos

Last Updated: Sep 10, 2025

Excitonic Hamiltonians for Calculating Optical Absorption Spectra and Optoelectronic Properties of Molecular Aggregates and Solids
08:04

Excitonic Hamiltonians for Calculating Optical Absorption Spectra and Optoelectronic Properties of Molecular Aggregates and Solids

Published on: May 27, 2020

8.5K
Isotopic Effect in Double Proton Transfer Process of Porphycene Investigated by Enhanced QM/MM Method
05:51

Isotopic Effect in Double Proton Transfer Process of Porphycene Investigated by Enhanced QM/MM Method

Published on: July 19, 2019

6.3K
Practical Aspects of Sample Preparation and Setup of 1H R1ρ Relaxation Dispersion Experiments of RNA
08:17

Practical Aspects of Sample Preparation and Setup of 1H R1ρ Relaxation Dispersion Experiments of RNA

Published on: July 9, 2021

4.8K

Area of Science:

  • Quantum chemistry
  • Computational chemistry
  • Theoretical chemistry

Background:

  • Symmetry-adapted perturbation theory (SAPT) is crucial for calculating intermolecular interaction energies.
  • First-order SAPT (SAPT(MC)) has been extended to include electron correlation effects.
  • Accurate calculation of exchange energies, especially double-exchange effects, remains a challenge.

Purpose of the Study:

  • To extend first-order multiconfigurational symmetry-adapted perturbation theory (SAPT(MC)) to incorporate double-exchange effects.
  • To develop density-matrix-based expressions for first-order exchange energy.
  • To evaluate the performance of these new methods for molecular interactions.

Main Methods:

  • Derivation of density-matrix-based expressions for first-order exchange energy.
  • Application of double-exchange approximation to strongly orthogonal geminal wave functions.
  • Development of an approximate method for double-exchange energy with complete active space (CAS) wave functions.

Main Results:

  • Successful extension of SAPT(MC) to account for double-exchange effects.
  • Numerical demonstration using strongly orthogonal geminal wave functions.
  • Analysis of approximate double-exchange energy evaluation with CAS wave functions on model dimers.

Conclusions:

  • The developed methods provide a more accurate treatment of intermolecular interactions by including double-exchange effects.
  • The proposed approximate method offers a practical approach for evaluating double-exchange energy in CAS wave functions.
  • The study advances the capability of SAPT(MC) for analyzing ground and excited states of molecular systems.