Mediaspace scheduled maintenance: Aug 25, 2026 07:00 - 12:00 AM. During this time, videos will be temporarily unavailable. Check status updates.

Lecture

Hybrid QM/MM Approaches

Description

This lecture introduces the Hybrid Quantum Mechanics/Molecular Mechanics (QM/MM) Approaches, covering topics such as partitioning the system, typical forms of MM potential, and practical implementation of QM/MM simulations. It explains the additive and subtractive schemes, the QM driver, and the QM/MM electrostatic interaction. The lecture also discusses the practical implementation of QM/MM simulations, the structure of the CPMD input file, and the importance of QM/MM consistency in electrostatics.

Official source

Related concepts (32)

Molecular dynamics

Molecular dynamics (MD) is a computer simulation method for analyzing the physical movements of atoms and molecules. The atoms and molecules are allowed to interact for a fixed period of time, giving a view of the dynamic "evolution" of the system. In the most common version, the trajectories of atoms and molecules are determined by numerically solving Newton's equations of motion for a system of interacting particles, where forces between the particles and their potential energies are often calculated using interatomic potentials or molecular mechanical force fields.

Molecular mechanics

Molecular mechanics uses classical mechanics to model molecular systems. The Born–Oppenheimer approximation is assumed valid and the potential energy of all systems is calculated as a function of the nuclear coordinates using force fields. Molecular mechanics can be used to study molecule systems ranging in size and complexity from small to large biological systems or material assemblies with many thousands to millions of atoms.

Computational chemistry

Computational chemistry is a branch of chemistry that uses computer simulation to assist in solving chemical problems. It uses methods of theoretical chemistry, incorporated into computer programs, to calculate the structures and properties of molecules, groups of molecules, and solids. It is essential because, apart from relatively recent results concerning the hydrogen molecular ion (dihydrogen cation, see references therein for more details), the quantum many-body problem cannot be solved analytically, much less in closed form.

Simulation

A simulation is the imitation of the operation of a real-world process or system over time. Simulations require the use of models; the model represents the key characteristics or behaviors of the selected system or process, whereas the simulation represents the evolution of the model over time. Often, computers are used to execute the simulation. Simulation is used in many contexts, such as simulation of technology for performance tuning or optimizing, safety engineering, testing, training, education, and video games.

Computer simulation

Computer simulation is the process of mathematical modelling, performed on a computer, which is designed to predict the behaviour of, or the outcome of, a real-world or physical system. The reliability of some mathematical models can be determined by comparing their results to the real-world outcomes they aim to predict. Computer simulations have become a useful tool for the mathematical modeling of many natural systems in physics (computational physics), astrophysics, climatology, chemistry, biology and manufacturing, as well as human systems in economics, psychology, social science, health care and engineering.

Related lectures (29)

Molecular Dynamics Simulations

Explores potential energy surfaces in molecular dynamics simulations and the use of mixed quantum mechanical/molecular mechanical methods.

Molecular dynamics under constraints

Explores molecular dynamics simulations under holonomic constraints, focusing on numerical integration and algorithm formulation.

Quantum Dynamics: Trajectory-Based Solutions

Explores quantum dynamics with trajectories and their applications in nonadiabatic dynamics and coupling with external fields.

QM/MM Hybrid Methods

Explores the integration of quantum mechanics and molecular mechanics in computational chemistry using CP2K software.

Efficient Stochastic Numerical Methods