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

Typical Model Studies01:30

Typical Model Studies

440
Fluid mechanics model studies often utilize scaled-down systems to predict fluid behavior in full-scale environments, such as river flows, dam spillways, and structures interacting with open surfaces. Maintaining Froude number similarity in river models is crucial, as it replicates surface flow features like wave patterns and velocities.
440
Wheatstone Bridge01:29

Wheatstone Bridge

666
An ohmmeter is a resistance-measuring device. It works by applying a voltage to a resistor of unknown resistance and measuring the current across the resistor. The resistance value is deduced using Ohm's law. Usually, the standard configuration of an ohmmeter comprises a voltmeter or an ammeter. However, such configurations are limited in accuracy because the meters alter the voltage applied to the resistor and the current that flows through it.
Thus, for accurate resistance measurements, a...
666
Simplified Synchronous Machine Model01:30

Simplified Synchronous Machine Model

329
The Synchronous Machine Model is a fundamental tool in analyzing and ensuring the transient stability of power systems. This model simplifies the representation of a synchronous machine under balanced three-phase positive-sequence conditions, assuming constant excitation and ignoring losses and saturation. The model is pivotal for understanding the behavior of synchronous generators connected to a power grid, particularly during transient events.
In this model, each generator is connected to a...
329
Linear Approximation in Time Domain01:21

Linear Approximation in Time Domain

124
Nonlinear systems often require sophisticated approaches for accurate modeling and analysis, with state-space representation being particularly effective. This method is especially useful for systems where variables and parameters vary with time or operating conditions, such as in a simple pendulum or a translational mechanical system with nonlinear springs.
For a simple pendulum with a mass evenly distributed along its length and the center of mass located at half the pendulum's length,...
124
The Small x Assumption02:20

The Small x Assumption

46.5K
If a reaction has a small equilibrium constant, the equilibrium position favors the reactants. In such reactions, a negligible change in concentration may occur if the initial concentrations of reactants are high and the Kc value is small. In such circumstances, the equilibrium concentration is approximately equal to its initial concentration.  This estimation can be used to simplify the equilibrium calculations by assuming that some equilibrium concentrations are equal to the initial...
46.5K
Improving Translational Accuracy02:07

Improving Translational Accuracy

2.7K
2.7K

You might also read

Related Articles

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

Sort by
Same author

Revisiting the C60ISO and iso-C60 Data Sets of Relative Energies for C<sub>60</sub> Isomers.

The journal of physical chemistry letters·2026
Same author

Link between Spin-Orbit Relativity and Magnetically Induced Current Densities in Heavy-Atom Hydrides: <i>trans</i>-Ligand Influence.

JACS Au·2026
Same author

Germylium Catalyzed Dehydrofluorination Reactions of Fluorinated Alkanes.

Chemistry (Weinheim an der Bergstrasse, Germany)·2026
Same author

An Energy-Corrected Fast Post-SCF Local-Hybrid Scheme for Highly Accurate Energy Differences of Large Main-Group Systems.

Journal of computational chemistry·2026
Same author

Routes to Cyclobutadiene and Cycloallyl Pt(II) Complexes: Dicationic Bis(Alkyne) Species as Intermediates.

Chemistry (Weinheim an der Bergstrasse, Germany)·2026
Same author

Evidence of orbital mixing upon ionization via Cooper minimum photoelectron dynamics in epichlorohydrin. Experiment and theory.

The Journal of chemical physics·2026

Related Experiment Video

Updated: Sep 11, 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

X2C Hamiltonian Models in ReSpect: Bridging Accuracy and Efficiency.

Michal Repisky1,2, Stanislav Komorovsky3, Lukas Konecny1,4,5

  • 1Hylleraas Centre for Quantum Molecular Sciences, Department of Chemistry, UiT The Arctic University of Norway, N-9037 Tromsø, Norway.

The Journal of Physical Chemistry. A
|August 18, 2025
PubMed
Summary
This summary is machine-generated.

The ReSpect program now offers advanced atomic mean-field exact two-component (X2C) models for simulating relativistic effects in spectroscopy. These new methods provide accurate and efficient alternatives to four-component calculations, enabling broader research applications.

More Related Videos

Setting Limits on Supersymmetry Using Simplified Models
07:46

Setting Limits on Supersymmetry Using Simplified Models

Published on: November 15, 2013

8.6K
X-ray Beam Induced Current Measurements for Multi-Modal X-ray Microscopy of Solar Cells
10:16

X-ray Beam Induced Current Measurements for Multi-Modal X-ray Microscopy of Solar Cells

Published on: August 20, 2019

14.0K

Related Experiment Videos

Last Updated: Sep 11, 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
Setting Limits on Supersymmetry Using Simplified Models
07:46

Setting Limits on Supersymmetry Using Simplified Models

Published on: November 15, 2013

8.6K
X-ray Beam Induced Current Measurements for Multi-Modal X-ray Microscopy of Solar Cells
10:16

X-ray Beam Induced Current Measurements for Multi-Modal X-ray Microscopy of Solar Cells

Published on: August 20, 2019

14.0K

Area of Science:

  • Quantum Chemistry
  • Computational Spectroscopy
  • Relativistic Quantum Mechanics

Background:

  • The ReSpect program has historically provided tools for spectroscopic simulations, including relativistic effects.
  • Previous advancements focused on one-electron exact two-component (X2C) Hamiltonian models.
  • Incorporating two-electron picture-change corrections is crucial for higher accuracy in relativistic calculations.

Purpose of the Study:

  • To introduce and theoretically establish two novel atomic mean-field X2C (amfX2C) models.
  • To present extended eamfX2C as a computationally efficient and accurate alternative to four-component relativistic methods.
  • To enable the simulation of complex spectroscopic phenomena previously limited by computational cost.

Main Methods:

  • Development of theoretical foundations for two distinct atomic mean-field X2C models.
  • Implementation of two-electron picture-change corrections within the X2C framework.
  • Focus on variational treatment of relativistic effects, particularly spin-orbit interactions.

Main Results:

  • Introduction of amfX2C and extended eamfX2C models.
  • Demonstration of computational efficiency and accuracy compared to four-component methods.
  • Enabling simulations of advanced spectroscopies like time-resolved pump-probe and cavity-modified molecular properties.

Conclusions:

  • The new amfX2C models offer significant improvements for relativistic calculations in spectroscopy.
  • ReSpect continues to evolve, providing state-of-the-art, free computational tools for researchers.
  • These advancements facilitate the exploration of relativistic effects in diverse scientific disciplines.