Quantum Chemistry

Quantum chemistry—more specifically, electronic structure theory—is the branch of molecular simulation which models the distribution of electrons about nuclei.

To run a quantum chemical calculation, one must specify a number of parameters:

• The identity and position of all atoms in one's molecule/molecules.
• The level of theory which the calculation will employ, which typically consists of a "method" and the basis set used to describe the electron distribution.
• The task you wish to perform (e.g. "energy," "forces," "dipole").
• (Optional) The specific settings to employ for the calculation, which in Rowan are grouped together into "modes."

To read more about how Rowan handles each of these parameters, check out the subsections to the left!

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Engines

Rowan supports quantum chemistry calculations through a number of underlying engines:

• Psi4 for Hartree–Fock and density-functional theory
• TeraChem for Hartree–Fock and density-functional theory
• PySCF for Hartree–Fock and density-functional theory
• xTB for semiempirical calculations
• AIMNet2 for machine-learned interatomic potential calculations

Support for additional engines is planned for the future!