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

Stability of Equilibrium Configuration: Problem Solving01:13

Stability of Equilibrium Configuration: Problem Solving

1.2K
The stability of equilibrium configurations is an important concept in physics, engineering, and other related fields. In simple terms, it refers to the tendency of an object or system to return to its equilibrium position after being disturbed. The stability of an equilibrium configuration can be analyzed by considering the potential energy function of the system and examining its behavior near the equilibrium point.
Problem-solving in the context of the stability of equilibrium configuration...
1.2K
Collisions in Multiple Dimensions: Problem Solving01:06

Collisions in Multiple Dimensions: Problem Solving

4.5K
In multiple dimensions, the conservation of momentum applies in each direction independently. Hence, to solve collisions in multiple dimensions, we should write down the momentum conservation in each direction separately. To help understand collisions in multiple dimensions, consider an example.
A small car of mass 1,200 kg traveling east at 60 km/h collides at an intersection with a truck of mass 3,000 kg traveling due north at 40 km/h. The two vehicles are locked together. What is the...
4.5K
Statically Indeterminate Problem Solving01:16

Statically Indeterminate Problem Solving

948
Statically indeterminate problems are those where statics alone can not determine the internal forces or reactions. Consider a structure comprising two cylindrical rods made of steel and brass. These rods are joined at point B and restrained by rigid supports at points A and C. Now, the reactions at points A and C and the deflection at point B are to be determined. This rod structure is classified as statically indeterminate as the structure has more supports than are necessary for maintaining...
948
Interference: Path Lengths01:10

Interference: Path Lengths

2.5K
Consider two sources of sound, that may or may not be in phase, emitting waves at a single frequency, and consider the frequencies to be the same.
Two special sources may be considered when they are in phase. This can be easily achieved by feeding the two sources from the same source. An example would be synchronizing the two speakers by feeding them with the same source, such as the sound waves produced by a tuning fork. This setup ensures that the two sources have the same frequency and are...
2.5K
Space Trusses: Problem Solving01:29

Space Trusses: Problem Solving

1.6K
A space truss is a three-dimensional counterpart of a planar truss. These structures consist of members connected at their ends, often utilizing ball-and-socket joints to create a stable and versatile framework. Due to its adaptability and capacity to withstand complex loads, the space truss is widely used in various construction projects.
Consider a tripod consisting of a tetrahedral space truss with a ball-and-socket joint at C. Suppose the height and lengths of the horizontal and vertical...
1.6K
Collisions in Multiple Dimensions: Introduction01:05

Collisions in Multiple Dimensions: Introduction

6.2K
It is far more common for collisions to occur in two dimensions; that is, the initial velocity vectors are neither parallel nor antiparallel to each other. Let's see what complications arise from this. The first idea is that momentum is a vector. Like all vectors, it can be expressed as a sum of perpendicular components (usually, though not always, an x-component and a y-component, and a z-component if necessary). Thus, when the statement of conservation of momentum is written for a...
6.2K

You might also read

Related Articles

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

Sort by
Same author

Correction to: Unraveling redox pathways of the disulfide bond in dimethyl disulfide: Ab initio modeling.

Journal of molecular modeling·2024
Same author

Unraveling redox pathways of the disulfide bond in dimethyl disulfide: Ab initio modeling.

Journal of molecular modeling·2024
Same author

Ultrafast Spectroscopy of Fe(II) Complexes Designed for Solar-Energy Conversion: Current Status and Open Questions.

Chemphyschem : a European journal of chemical physics and physical chemistry·2022
Same author

First-principles characterization of the singlet excited state manifold in DNA/RNA nucleobases.

Physical chemistry chemical physics : PCCP·2020
Same author

Localized Molecular Orbital-Based Embedding Scheme for Correlated Methods.

Journal of chemical theory and computation·2020
Same author

Characterization of Conjugation Effects in the Series of Quinoxaline-2-ones by Means of Vibrational Raman Spectroscopy.

The journal of physical chemistry. A·2020

Related Experiment Video

Updated: May 4, 2026

The Spatial Memory Game: Testing the Relationship Between Spatial Language, Object Knowledge, and Spatial Cognition
05:15

The Spatial Memory Game: Testing the Relationship Between Spatial Language, Object Knowledge, and Spatial Cognition

Published on: February 19, 2018

12.0K

Multireference space without first solving the configuration interaction problem.

Vitaly N Glushkov1, Xavier Assfeld

  • 1Department of Physics, Electronics and Computer Systems, Oles Gonchar Dnipropetrovsk National University, Dnipropetrovsk, Ukraine.

Journal of Computational Chemistry
|January 10, 2014
PubMed
Summary

This study introduces a new computational method for calculating excited states (ESs) in molecules. The approach simplifies generating reference spaces, enabling more efficient and accurate calculations of molecular electronic structures.

Keywords:
correlation energyexcited statesmultireference perturbation theoryorthogonality constraints

More Related Videos

Dissociation of the Confounding Influences of Expectancy and Integrative Difficulty Residing in Anomalous Sentences in Event-related Potential Studies
05:22

Dissociation of the Confounding Influences of Expectancy and Integrative Difficulty Residing in Anomalous Sentences in Event-related Potential Studies

Published on: May 9, 2019

4.7K
Implementation of a Reference Interferometer for Nanodetection
16:11

Implementation of a Reference Interferometer for Nanodetection

Published on: April 26, 2014

8.8K

Related Experiment Videos

Last Updated: May 4, 2026

The Spatial Memory Game: Testing the Relationship Between Spatial Language, Object Knowledge, and Spatial Cognition
05:15

The Spatial Memory Game: Testing the Relationship Between Spatial Language, Object Knowledge, and Spatial Cognition

Published on: February 19, 2018

12.0K
Dissociation of the Confounding Influences of Expectancy and Integrative Difficulty Residing in Anomalous Sentences in Event-related Potential Studies
05:22

Dissociation of the Confounding Influences of Expectancy and Integrative Difficulty Residing in Anomalous Sentences in Event-related Potential Studies

Published on: May 9, 2019

4.7K
Implementation of a Reference Interferometer for Nanodetection
16:11

Implementation of a Reference Interferometer for Nanodetection

Published on: April 26, 2014

8.8K

Area of Science:

  • Quantum Chemistry
  • Computational Chemistry
  • Theoretical Spectroscopy

Background:

  • Accurate calculation of molecular excited states (ESs) is crucial for understanding photophysical processes.
  • Existing methods for generating multireference spaces can be computationally intensive, especially for excited states.
  • Previous work established a method for ground state (GS) calculations but required solving the configuration interaction problem.

Purpose of the Study:

  • To develop a computationally efficient method for calculating low-lying excited states (ESs) with the same symmetry as the ground state (GS).
  • To extend the concept of compact multireference space generation to excited states without prior configuration interaction calculations.
  • To introduce a two-reference Møller-Plesset (MP) like perturbation theory tailored for excited states.

Main Methods:

  • A novel two-reference Møller-Plesset (MP)-like perturbation theory is developed for excited states (ESs).
  • The method utilizes a main reference configuration from excited state (ES)-adjusted molecular orbitals and secondary double excitations from ground state (GS)-like orbitals.
  • Modifications to the MP zeroth-order Hamiltonian ensure compatibility with orthogonality conditions and proper treatment of reference configurations and excitations.

Main Results:

  • The proposed scheme successfully generates compact multireference spaces for excited states (ESs).
  • The modified zeroth-order Hamiltonian ensures that reference configurations and excitations are eigenfunctions and satisfy orthogonality constraints.
  • The method is applied to calculate ground state (GS), excited state (ES), and excitation energies for small molecules, demonstrating its validity and accuracy.

Conclusions:

  • The developed two-reference Møller-Plesset (MP)-like perturbation theory provides an efficient approach for calculating molecular excited states (ESs).
  • The method avoids the need for computationally expensive configuration interaction calculations for generating multireference spaces.
  • The scheme is applicable to various molecular systems, offering a valuable tool for theoretical spectroscopy and computational chemistry.