Efficient Excited-State Quantum Chemical Calculations of Large Molecules – running

The accurate theoretical modeling of excited state properties (electronic excitation energy, UV-visible spectra) of molecular systems is limited by the severe computational requirements of the presently available quantum chemical methods. Reasonably accurate calculations can only be performed for systems containing at most about 50 atoms within reasonable computation time. Our goal is to develop approximate algorithms which can significantly reduce the computational costs, while preserving the intrinsic accuracy of the exact methods. We introduce better algorithms and approximations on the basis of numerical mathematical methods, and carry out transformations controlled by specific physical or chemical considerations, where we can effectively reduce the number of variables, such as the number of molecular orbitals, leading to a drastic reduction in the computational demand. The schemes are available for the scientific community as part of the MRCC program suite developed in our laboratory. The approximations can be employed for the calculation of excitation energies and absorption- or circular dichroism spectra in the organic, biomolecular and photochemical fields, and to investigate the rearrangement in the charge distribution upon excitation, or to identify the molecular orbitals characteristic of the excitation.

Project owner:
Mester Dávid (Fizikai Kémia és Anyagtudományi Tanszék)
Web address:
Fizikai Kémia és Anyagtudományi Tanszék (VBK-FKAT)

Élvonal - Kutatói kiválósági program (KKP126451)