Methods based on the multireference perturbation theory (MRPT) with the one-electron zeroth-order Hamiltonian are widely used for the description of excited states, for example, due to their relatively low computational cost. However, current methods have a common drawback-use of a model space with low size. In this article, we propose the MRPT method with the model space extended to the complete active space.
View Article and Find Full Text PDFModeling of the excited states of multichromophoric systems is crucial for the understanding of photosynthesis functioning. The excitonic Hamiltonian method is widely used for such calculations. Excited states of the combined system are constructed from the wave functions of individual chromophores while their interactions are described by excitonic couplings.
View Article and Find Full Text PDFCalculation of the excited states properties of pigment complexes is one of the key problems in the photosynthesis research. The excited states of LH1 complex of Thermochromatium tepidum were studied by means of the high-precision quantum chemistry methods. The influence of different parameters of the calculation procedure was examined.
View Article and Find Full Text PDFPrimary electron transfer (ET) in the chromophore subsystem in a bacterial reaction center (RC) is a unique process, and is coupled with the protein motion, which, like the ET, is caused by photoexcitation of these chromophores. ET is also coupled with dissipative processes, which are caused by interaction between chromophores and vibrations of its surrounding protein. We propose a new dynamics calculation method that accounts for both these effects of protein vibrations.
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