Tutorials, recipes, and on-line resources

Massive Open Online Course (MOOC)

The theory behind classical and path-integral methods for structure and dynamics along with practical exercises can be found in an online course freely available to everyone, and accessible from this link.

i-PI resources

For more information about i-PI and to download the source code go to http://ipi-code.org/.

In http://gle4md.org/ one can also obtain colored-noise parameters to run Path Integral with Generalized Langevin Equation thermostat (PI+GLE/PIGLET) calculations.

Examples and demos

The examples and demos folders in the i-PI source code contain inputs for many different types of calculations based on i-PI. Examples are typically minimal use-cases of specific features, examples of client codes, or setups for high performance computing, while demos are more structured, tutorial-like examples that show how to realize more complex setups, and also provide a brief discussion of the underlying algorithms.

To run these examples, you should typically start i-PI, redirecting the output to a log file, and then run a couple of instances of the driver code. The progress of the wrapper is followed by monitoring the log file with the tail Linux command.

Optionally, you can make a copy of the directory with the example somewhere else if you want to keep the i-PI directory clean. For example:

bash
cd demos/para-h2-tutorial/tutorial-1/
i-pi tutorial-1.xml > log &
i-pi-driver -a localhost -p 31415 -m sg -o 15 &
i-pi-driver -a localhost -p 31415 -m sg -o 15 &
tail -f log

Tutorials

A simple tutorial on how to run i-PI can be found in the documentation: a simple tutorial.

You can try a set of guided examples that demonstrate some more advanced features of i-PI. These Tutorials, from the 2021 CECAM Flagship school, are available here: i-PI 2021 tutorials.

Tutorials from the 2023 CECAM Flagship school are available here: i-PI 2023 tutorials.

Tutorial from one of our developers on using machine learning interatomic potentials with i-PI are available here: MLIPs-with-i-PI.

Note that these examples use some features (such as qTIP4P/F water and the Zundel cation potentials in the driver code, and optionally also CP2K). Instructions on how to install and run these codes with i-PI are contained in the tutorial.

Atomistic recipes

Several examples of usage of i-PI to perform advanced molecular simulations can be found among the recipes of the atomistic cookbook. These include an introduction to path integral simulations, a discussion of how to compute quantum heat capacities, and an example of path integral metadynamics.