Research interest / own contributions

Toggle Background

During my Ph.D. thesis I wrote an individually selecting MRCI program [1] (DIESEL-CI: direct internal external individually selecting CI). The DIESEL package implements the selection and energy extrapolation schemes according to the following scheme

as given by [2,3].

Major benefits of DIESEL-MRCI

• n^1.5 scaling in the number of selected CSFs (former scaling: n² $\Longrightarrow$ significant speed up in comparison to former program packages (factor 10 at 80000 CSFs))
• Automatization of a multi-reference calculation
• Interface to MOLCAS and CHARMM
• Parallel implementation
• Density matrices
• Property calculation
• Generation of natural orbitals
• Various selection schemes (Epstein Nesbet, Møller Plesset, random)
• Very flexible excitation engine (orbital restrictions)
• Symmetrization features

The DIESEL package has been used by many different groups (Universities of Bonn, Cologne, Würzburg, Heidelberg, Potsdam, Mülheim, Leiden, Carleton, New Brunswick, Praha) and many publications rely on this package. The DIESEL package furthermore includes multi-reference perturbation theory which will be described below.