Related Experiment Video
Updated: Jun 20, 2026
12:11
Computation of Atmospheric Concentrations of Molecular Clusters from ab initio Thermochemistry
Published on: April 8, 2020
Dispersion-corrected Møller-Plesset second-order perturbation theory.
Alexandre Tkatchenko1, Robert A DiStasio, Martin Head-Gordon
1Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany. atkatchenko@gmail.com
The Journal of Chemical Physics
|September 11, 2009
Summary
Researchers improved Møller-Plesset second-order perturbation theory (MP2) for molecular dispersion interactions. The new MP2 + Delta vdW method accurately predicts binding energies, outperforming current density-functional theory approaches.
Area of Science:
- Computational Chemistry
- Quantum Chemistry
- Theoretical Chemistry
Background:
- Møller-Plesset second-order perturbation theory (MP2) often shows limitations in accurately describing dispersion interactions between closed-shell molecules.
- Accurate calculation of dispersion forces is crucial for understanding molecular interactions in various chemical systems.
Purpose of the Study:
- To enhance the accuracy of MP2 theory for dispersion interactions.
- To develop a robust and reliable method for calculating non-covalent interactions.
Main Methods:
- A correction term, Delta C(n)/R(n), was added to the long-range behavior of MP2.
- The performance of the dispersion-corrected MP2 (MP2 + Delta vdW) method was evaluated against the CCSD(T) "gold standard" and dispersion-corrected density-functional theory.
Main Results:
- The MP2 + Delta vdW method demonstrated excellent agreement with CCSD(T) results for systems involving hydrogen bonding, electrostatics, and dispersion.
- The method showed mild dependence on the choice of short-range damping function.
- MP2 + Delta vdW consistently outperformed state-of-the-art dispersion-corrected density-functional theory methods.
Conclusions:
- The addition of a long-range correction significantly improves the MP2 description of dispersion interactions.
- MP2 + Delta vdW offers a computationally efficient and accurate alternative for studying molecular interactions.
- This enhanced MP2 method provides a reliable tool for computational chemistry research.
More Related Videos
Related Concept Videos
03:51Molecular Orbital Theory II
Molecular Orbital Energy Diagrams
01:02¹H NMR: Interpreting Distorted and Overlapping Signals
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 slanted or...
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 slanted or...
01:18Second Order systems II
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.
If ζ...
If ζ...
01:22Second Derivatives and Laplace Operator
The first order operators using the del operator include the gradient, divergence and curl. Certain combinations of first order operators on a scalar or vector function yield second order expressions. Second-order expressions play a very important role in mathematics and physics. Some second order expressions include the divergence and curl of a gradient function, the divergence and curl of a curl function, and the gradient of a divergence function.
Consider a scalar function. The curl of its...
Consider a scalar function. The curl of its...
02:35Molecular Orbital Theory I
Overview of Molecular Orbital Theory
01:20¹³C NMR: Distortionless Enhancement by Polarization Transfer (DEPT)
When proton-coupled carbon-13 spectra are simplified by a broadband proton decoupling technique, structural information about the coupled protons is lost. Distortionless enhancement by polarization transfer (DEPT) is a technique that provides information on the number of hydrogens attached to each carbon in a molecule. While the DEPT experiment utilizes complex pulse sequences, the pulse delay and flip angle are specifically manipulated. The resulting signals have different phases depending on...