Psi4 is an open-source suite of ab initio quantum chemistry programs designed for efficient, high-accuracy simulations of a variety of molecular properties. It’s written in C++ driven by Python.
Psi4 provides a wide variety of quantum chemical methods using state-of-the-art numerical methods and algorithms. Several parts of the code feature shared-memory parallelization to run efficiently on multi-core machines. An advanced parser written in Python allows the user input to have a very simple style for routine computations, but it can also automate very complex tasks with ease.
Psi4 can perform ab initio computations employing basis sets of contracted Gaussian-type functions of virtually arbitrary orbital quantum number. Many parts of PSI4 can recognize and exploit the largest Abelian subgroup of the molecular point group. Table Methods displays the range of theoretical methods available in PSI4. For more details, see Tables Energy, Energy (DFT), Energy (MRCC), Energy (CFOUR), Gradient, Gradient (CFOUR), and Frequency.
It is very easy to use and has an optional Python interface.
Features include:
- Several formulations of newly-developed density cumulant functional theory (DCFT).
- Highly optimized code for full configuration interaction and highly correlated configuration interaction.
- Coupled cluster.
- Production-level Mukherjee-style state-specific coupled-cluster theory, including perturbative triples and also associated multi-reference perturbation theories.
- Extremely efficient code to perform wavefunction-based Symmetry Adapted Perturbation Theory (SAPT).
- Orbital-Optimized Post-Hartree–Fock Methods.
- Second-Order Algebraic-Diagrammatic Construction.
- Density Matrix Renormalization Group.
- Scalar Relativistic Corrections.
Website: www.psicode.org
Support: Manual, FAQ, Forum, GitHub Code Repository
Developer: The Psi4 Developers
License: GNU Lesser General Public License
Psi4 is written in C++ and Python. Learn C++ with our recommended free books and free tutorials. Learn Python with our recommended free books and free tutorials.
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