Force Field X

Force Field X is an atomic resolution molecular modeling application that targets open research questions in the areas of:

• predicting the structure, thermodynamic stability and solubility of organic polymer crystals,
• predicting the effect of missense mutations on protein structure, thermodynamics and molecular phenotype
• computational design of biomolecules in both soluble and crystalline environments

Please see the Force Field X website for more details.

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Use Binder to Try Force Field X Online

With Java

With Kotlin

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Clone Force Field X

To clone the Force Field X source using GIT:

git clone git@github.com:SchniedersLab/forcefieldx.git forcefieldx

In the future, your clone of Force Field X can be updated to the latest version using the command:

git pull origin master

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Build Using Maven

A Maven project file (pom.xml) is provided to build Force Field X on any platform. After cloing the Force Field X git repository, change directories into the base project directory. Then execute:

./mvnw

This will download and execute Maven. The first time this command is executed, build dependencies and Force Field X runtime dependencies will be downloaded. Future executions are quicker. Force Field X will self-test its modules and report failures. Only code that passes all testing should be pushed to the GitHub repository, so if any test fails it may be due to a local configuration issue. To execute the tests:

./mvnw -DskipTests=false

Additional tests, ordinarily skipped due to length of running them (~15 minutes on a single core of a 2013 CPU) can be accessed via the ffx.ci property, as such:

./mvnw -DskipTests=false -Dffx.ci=true

Currently, JDK 21 through JDK 25 are supported. After installing a supported JDK, point the JAVA_HOME environment variable to the JDK directory, and then add the JDK bin directory to your path.

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Execute Force Field X

Once the Maven build succeeds, Force Field X can be executed using platform dependent start-up scripts located in the bin. On Mac OS X or Linux:

bin/ffxc Energy examples/alamet.xyz

On Windows:

bin/ffxc.bat Energy examples/alamet.xyz

The ffx/bin directory should be appended to your $PATH environment variable. The "Energy" command refers to an internal version of the Energy.groovy script that can be found in the ffx/scripts directory. To embed your own script within FFX, place it into the scripts directory and rebuild FFX.