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

Magnetic Field due to Moving Charges01:23

Magnetic Field due to Moving Charges

A stationary charge creates and interacts with the electric field, while a moving charge creates a magnetic field.
Consider a point charge moving with a constant velocity. Like the electric field, the magnetic field at any point is directly proportional to the magnitude of the charge and inversely proportional to the square of the distance between the source point and the field point. However, unlike the electric field, the magnetic field is always perpendicular to the plane containing the line...
Average Velocity01:12

Average Velocity

To calculate the other physical quantities in kinematics, we must introduce the time variable. The time variable allows us not only to state the position of the object during its motion, but also how fast it is moving. The speed at which an object is moving is given by the rate at which the position changes with time. For each position xi, we assign a particular time ti. If the details of the motion at each instant are not important, the rate is usually expressed as the average velocity. This...
Root Mean Square00:57

Root Mean Square

If in an experiment, data values have a probability of being both positive and negative, neither the arithmetic mean, the geometric mean, nor the harmonic mean can be used to calculate the central tendency of the data set. In particular, if the positive and negative values are equally likely, the arithmetic mean is close to zero.
For example, consider the velocity of gas molecules in a container. The gas molecules are moving in different directions, which might impart positive and negative...
The Principle of Superposition and the Gravitational Field01:17

The Principle of Superposition and the Gravitational Field

The principle of superposition applies to gravitational forces of objects that are sufficiently far apart. It states that the net gravitational force on a point object is the vector sum of the gravitational forces on it due to various objects. The principle helps calculate the force by listing the individual forces and then vectorially summing them up. However, it should be noted that the principle of superposition is not always apparent. In the presence of a second force, the first force could...
Center of Mass: Introduction01:03

Center of Mass: Introduction

Any object that obeys Newton's second law of motion is made up of a large number of infinitesimally small particles. Objects in motion can be as simple as atoms or as complex as gymnasts performing in the Olympics. The motion of such objects is described about a point called the center of mass of the object. The center of mass of an object is a point that acts as if the whole mass is concentrated at that point. The center of mass of an object with a large number of infinitesimally small...
The Mean Value Theorem01:26

The Mean Value Theorem

The Mean Value Theorem establishes a fundamental connection between the overall change in a quantity and its change at a specific instant. It formalizes the idea that average change over an interval must be reflected by instantaneous change at some point within that interval. When a function behaves smoothly across a range, the theorem guarantees that this connection always exists.This relationship is captured mathematically by the Mean Value Theorem, as stated below.The meaning of this result...

You might also read

Related Articles

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

Sort by
Same author

Comprehensive Characterization of <i>BrSULTRs</i> Family and Their Expression Profiles Under Salt and Low-Temperature Stresses.

Genes·2026
Same author

Surface-Assisted Wurtz Coupling for the Stereoselective Synthesis of Covalent Organic Frameworks.

Angewandte Chemie (International ed. in English)·2026
Same author

Ladder-Type Covalent Organic Frameworks with Highly Delocalized π-Electrons and Dense Redox-Active Sites toward Robust Aqueous Iron Organic Batteries.

Advanced materials (Deerfield Beach, Fla.)·2025
Same author

Donor-Acceptor Porous Aromatic Framework Cathode with Fast Redox Kinetics for Ultralow-Temperature (-70 °C) Potassium-Organic Batteries.

Angewandte Chemie (International ed. in English)·2025
Same author

Reversible surface reconstruction of metal-organic frameworks for durable oxygen evolution reaction.

Chemical science·2025
Same author

Efficient photocatalytic C-3 thiocyanation of indoles over tetraphenylsilane-based porous aromatic frameworks.

Chemical communications (Cambridge, England)·2025

Related Experiment Video

Updated: May 11, 2026

Analyzing Melts and Fluids from Ab Initio Molecular Dynamics Simulations with the UMD Package
06:37

Analyzing Melts and Fluids from Ab Initio Molecular Dynamics Simulations with the UMD Package

Published on: September 17, 2021

Mean field QM/MM method: average position approximation.

Fengchao Cui1, Hui Li

  • 1Department of Chemistry, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, USA.

The Journal of Chemical Physics
|May 10, 2013
PubMed
Summary
This summary is machine-generated.

The average position mean field combined quantum mechanics/molecular mechanics (QM/MM) method speeds up simulations but has errors. Using a polarizable force field for the QM region is crucial for accurate and efficient QM/MM simulations.

More Related Videos

Frequency Mixing Magnetic Detection Scanner for Imaging Magnetic Particles in Planar Samples
07:01

Frequency Mixing Magnetic Detection Scanner for Imaging Magnetic Particles in Planar Samples

Published on: June 9, 2016

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

Related Experiment Videos

Last Updated: May 11, 2026

Analyzing Melts and Fluids from Ab Initio Molecular Dynamics Simulations with the UMD Package
06:37

Analyzing Melts and Fluids from Ab Initio Molecular Dynamics Simulations with the UMD Package

Published on: September 17, 2021

Frequency Mixing Magnetic Detection Scanner for Imaging Magnetic Particles in Planar Samples
07:01

Frequency Mixing Magnetic Detection Scanner for Imaging Magnetic Particles in Planar Samples

Published on: June 9, 2016

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

Area of Science:

  • Computational Chemistry
  • Molecular Dynamics
  • Quantum Mechanics

Background:

  • Combined quantum mechanics/molecular mechanics (QM/MM) methods are essential for simulating complex molecular systems.
  • Mean field QM/MM approaches offer computational efficiency but may sacrifice accuracy.

Purpose of the Study:

  • To describe the average position mean field QM/MM method.
  • To analyze the accuracy and efficiency of QM/MM simulations.
  • To identify sources of error in QM/MM calculations.

Main Methods:

  • Development and application of the average position mean field QM/MM method.
  • Rigorous analysis of errors in QM/MM simulations.
  • Comparison of different QM/MM approaches.

Main Results:

  • The average position mean field QM/MM method significantly reduces simulation time, enabling sampling of millions of configurations.
  • A general and significant error (up to 7 kcal/mol) was identified in mean field QM/MM methods.
  • This error originates from the loss of instantaneous polarization in the QM electronic wavefunction.

Conclusions:

  • Mean field QM/MM methods, while efficient, suffer from polarization errors.
  • Accurate and efficient QM/MM simulations require the use of polarizable force fields for the QM region.