The structure and dynamics of molecular systems in ground and excited electronic states

The subject of the proposed project are molecules of different dimensions: from small ones, radicals and ions that were identified in interstellar space, to larger molecules that are significant for biological systems. We shall use the tools of quantum mechanics in order to describe the states and processes that take place in them: ab initio methods that include electronic structure methods (for desciption of ground and excited states), variational and perturbational approaches to the nuclear problem, as well as the methods of quantum dynamics. We are planning the modeling of infrared spectra, calculation of vibronic levels in spatially and spin degenerate electronic states, determination of transition moments between vibronic states of interest, determination of inter-system rates, in other words the prediction of spectra that are not recorded as well as the interpretation of the existing ones. The structure and dynamics of concrete and relevant molecular systems will be analyzed; these are the species that have recently been identified in the interstellar space and their structural parameters have not yet been determined. We are also going to analyze the systems that are important for living world. In order to accomplish that aim we plan not only to use the existing programs (some of them were developed by ourselves), but also to extend them. The expected results will be of relevance for broad scientific community in the field ranging from astrophysics to biology.