*Quantum Package* is an open-source programming environment for quantum
chemistry, which was built for developpers in order to help the design of new
computational methods, especially in the field of wave function theory.

From the user point of view, *Quantum Package* proposes a stand-alone path to
use optimized selected configuration interaction methods based on the CIPSI
algorithm that can efficiently approcah full CI quality for relatively large
systems.


* [Download the source code](http://github.com/QuantumPackage/qp2)
* [Read the documentation](https://quantum-package-scemamamaster.readthedocs.io/)
* [Try it now in your web browser](/page/try)