Kurzbeschreibung
(Englisch)
|
In 1993 [1], we demonstrated that the embedding potential applied in various computational methods, in which it is expressed by means of system-specific parameters, has the exact system-independent form relying on universal density functionals. This provided a formal basis for a number of computational methods developed subsequently by us and others. It resulted also in a development in a new subdomain in quantum many-body theory (see Refs. [1-7]), which we refer to as Frozen-Density-Embedding Theory (FDET). Our recent research focus on electronic excitations: we made necessary extensions of the ground-state version of FDET to excited states [6,10] beased on the Linear-Response TDDFT Ansatz, developed and tested approximations [4,8], and demonstrated high-accuracy of the developed method in benchmark calculations [12]. As a result, we can predict the effect of a non-covalently bound environment on electronic states of embedded chromophores with very high accuracy (errors in the range of 100 cm-1). We plan to improve the numerical efficiency of already existing simulation techniques and apply them for systems investigated by our COST partners for such properties as electron spin resonance spectra of radicals embedded in proteins and electronic excitations of organic chromophores in liquids and proteins. We plan also to adopt the existing FDET based methods to simulate the emission spectra.
|
Abstract
(Englisch)
|
In the final reporting period, we achieved the goals of the project. Several computational protocols based on Frozen Density Embedding Theory (FDET) [1,2,3] for modeling spectroscopic properties of embedded species were developed and tested for specific systems and properties. Development of a method for simulating solvatochromism of emission in the UV/Vis range by means of the non-uniform continuum model within FDET introduced earlier for modeling solvatochromism in absorption [4] and the FDET based method for simulating electric field gradients for interpreting quadrupole splittings in the NMR spectra of embedded species, are principal methodological achievements of the current reporting period. Dr. S. Shedge whose position was funded by the SERI grant was instrumental in these developments. Several international collaborations were established. They concerned various applications of FDET based methods and lead to a publication (modelling fine-tuning of the color of embedded retinal with Profs. D. Sundholm - Helsinki and V. Kaila - Munich), publication in preparation (simulating of electric field gradients with Dr. T. Mineva - Montpellier), and several projects which are expected to continue beyond the scope of the reporting period (modeling of solvatchromism of UV/Vis emission/absorption spectra with Profs. K.V. Mikkelsen- Copenhagen, V. Barone - Pisa, and M.E. Casida - Grenoble). [1] T.A. Wesolowski and A. Warshel, J. Phys. Chem. (1993) 97, 8050 [2] T.A. Wesolowski, Phys. Rev. A. (2008) 77, 012504 [3] T.A. Wesolowski, J. Am. Chem. Soc., (2004) 126, 11444 [4] J.W. Kaminski, S. Gusarov, A. Kovalenko, T.A. Wesolowski, J. Phys. Chem. A (2010) 114, 6082
|
