Dalton ab initio quantum chemistry software is designed to allow convenient, automated determination of a large number of molecular properties based on an HF, HF-srDFT, DFT, MP2, CC, CI, MCSCF, or MC-srDFT reference wave function.
Additions to the Dalton 2.0 release included density functional theory implemented
fully up to quadratic response theory for closed-shell systems, as well as second derivatives for properties involving perturbation-dependent basis sets such a molecular Hessians, magnetizabilities and nuclear shieldings.
Also available from later releases are the NEVPT2 approach (the n-electron valence second-order perturbation theory) for calculating accurate energetics of CASSCF or CAS-srDFT multireference-based systems including also dynamic electron correlation, a parallel large-scale multireference CI program based on the concept of Generalized Active Spaces, and highly accurate MP2-R12 methods are available for highaccuracy energetics of single-reference dominated closed-shell systems.
The program consists of seven separate components, developed more or less independently. Hermit is the integral generator, generating ordinary atomic and molecular integrals appearing in the time-independent, non-relativistic Schr¨odinger equation, as well as an extensive number of integrals related to different molecular properties. eri is a vectorized and distribution-oriented integral generator that may be invoked in certain calculations, in particular in integral-direct coupled cluster calculations.
