Quantum Package is an open-source programming environment for quantum chemistry specially designed for wave function methods. Its main goal is the development of determinant-driven selected configuration interaction (sCI) methods and multi-reference second-order perturbation theory (PT2).

The determinant-driven framework allows the programmer to include any arbitrary set of determinants in the reference space, hence providing greater methodological freedoms. The sCI method implemented in Quantum Package is based on the CIPSI (Configuration Interaction using a Perturbative Selection made Iteratively) algorithm which complements the variational sCI energy with a PT2 correction. Additional external plugins have been recently added to perform calculations with multireference coupled cluster theory and range-separated density-functional theory.

Quantum Package 2.0: An Open-Source Determinant-Driven Suite of Programs
Yann Garniron, Thomas Applencourt, Kevin Gasperich, Anouar Benali, Anthony Ferté, Julien Paquier, Barthélémy Pradines, Roland Assaraf, Peter Reinhardt, Julien Toulouse, Pierrette Barbaresco, Nicolas Renon, Grégoire David, Jean-Paul Malrieu, Mickaël Véril, Michel Caffarel, Pierre-François Loos, Emmanuel Giner, Anthony Scemama
https://arxiv.org/abs/1902.08154

Full-CI calculation

 Posted on February 5, 2019
Enter in qpsh mode for auto completion ~/your_path_to_qp/bin/qpsh Create an EZFIO DATA BASE from .xyz qp create_ezfio -b 6-31g hcn.xyz # output:: hcn.ezfio DATA BASE Run a HF calculation on the EZFIO qp run scf | tee output_file.scf.out # output:: create MO basis in the EZFIO Freeze the 1s orbitals in the EZFIO qp set_frozen_core Run the CIPSI algorithm on the EZFIO qp run fci | tee output_file. [Read More]

Hartree-Fock calculation

 Posted on February 4, 2019
  1. Enter in qpsh mode for auto completion
~/your_path_to_qp/bin/qpsh
  1. Create an EZFIO DATA BASE from .xyz
qp create_ezfio -b 6-31g hcn.xyz
  1. Run a HF calculation on the EZFIO and put the output in a file
qp run scf | tee hcn.ezfio.scf.out

Installation

 Posted on February 3, 2019
Download the source files git clone https://github.com/QuantumPackage/qp2.git Install the dependencies ./configure # tells you what to install. See in INSTALL.rst USE AT YOUR OWN RISK, NO SUPPORT WILL BE PROVIDED ./configure --install something The following libraries are needed for the ocaml package zlib1g-dev libncurses5-dev pkg-config libgmp3-dev m4 Once the smiling cow appears, load the environment variables [Read More]