Related Experiment Video
Updated: Feb 11, 2026

An All-in-one Sample Holder for Macromolecular X-ray Crystallography with Minimal Background Scattering
Published on: July 6, 2019
Accelerated Enveloping Distribution Sampling: Enabling Sampling of Multiple End States while Preserving Local Energy
Jan Walther Perthold1, Chris Oostenbrink1
1Institute for Molecular Modeling and Simulation, Department for Material Sciences and Process Engineering , University of Natural Resources and Life Sciences (BOKU), Vienna , Muthgasse 18 , 1190 Vienna , Austria.
Enveloping distribution sampling (EDS) enables calculating multiple free-energy differences from one molecular dynamics (MD) simulation. This new method improves EDS Hamiltonian construction for robust, automated free-energy calculations.
Area of Science:
- Computational chemistry
- Statistical mechanics
- Molecular dynamics simulations
Background:
- Enveloping distribution sampling (EDS) is an efficient method for calculating multiple free-energy differences.
- Constructing an effective reference-state Hamiltonian for EDS is challenging.
- Existing EDS methods may not efficiently sample all relevant states.
Purpose of the Study:
- To develop a novel approach for constructing the EDS reference-state Hamiltonian.
- To preserve local energy minima of end-states within the EDS framework.
- To introduce an intuitive and robust parameter optimization scheme for EDS.
Main Methods:
- Proposed a novel reference-state Hamiltonian construction for EDS, building on energy landscape smoothing techniques.
- Ensured the reference-state Hamiltonian preserves local energy minima of combined end-states.
- Developed an intuitive, robust, and efficient parameter optimization scheme for EDS Hamiltonian parameters.
Main Results:
- Demonstrated the proposed EDS method on established and novel test systems.
- Showcased the ability to automate the calculation of multiple free-energy differences from a single simulation.
- Validated the preservation of local energy minima in the reference-state Hamiltonian.
Conclusions:
- The novel EDS approach facilitates automated calculation of multiple free-energy differences.
- The method is robust, user-friendly, and grounded in statistical mechanics principles.
- Accelerated EDS offers a reliable tool for computing free-energy differences.
Related Concept Videos
Sampling Distribution
Sampling Methods: Sample Types
Solid samples include a variety of substances, such as sediments from water bodies, soil, metals, and biological tissues. Two standard methods for extracting sediments from water bodies are grab sampling and piston coring. Grab sampling involves using a device to collect a discrete sediment sample from the bottom of a water body with minimal disturbance. Grab samples do not always represent the entire area due to...
Energy Associated With a Charge Distribution
Sampling Plans
Random sampling is a method where each member of the population has an equal chance of being selected for the sample. It involves selecting individuals randomly, often using random number generators or lottery-type methods. For example, when analyzing the properties of a...
Sample Handling
Samples should be transported carefully from collection points to the laboratory. They should be properly sealed and clearly labeled to prevent cross-contamination. To preserve the sample integrity, optimal temperature conditions during transport are essential. This could involve using...
Sampling Theorem

