Currently, I am working on my PhD, which is in the field of X-ray science. Mainly it deals with simulations of a variety of X-ray spectra - XPS, NEXAFS, resonant Auger, and vibronic contributions to them. Systems of interest are naphthalene, biphenyl, water clusters etc. We are using quantum chemistry to obtain some important properties of the system - vibrational frequencies, transition dipole moments, gradients of the potential energy surface, for both ground and excited states. For the purpose, different codes are used - DALTON, deMon, Gaussian. Then the obtained numbers are plugged into well known expressions of the respective cross-section, and if everything goes according to plan, a spectrum is obtained. Our work is in close colaboration with experimental groups, so we have the opportunity to compare our simulations against the reality. In this way, we learn more about the physics of the investigated process, explain experimental data or predict yet unobserved effect.
| Until now, I have been working on several problems - interplay between vibrational structure and chemical shifts in naphthalene and biphenyl, anomalously big vibrational broadening in the XPS of water dimer, interference effects in resonant Auger spectrum of ordered homonuclear molecules. |  |
Currently, together with Sergey Polyutov we're working on a new project,concerning non-linear optical properties of some promising two-photon chromophores. Basically, we're trying to explain an experimentally observed effect - difference between the linear and two-photon spectra in the visible/near-IR region.
More information about my work you can find in some of my
papers.
More about the research activities in our group, you can find on the
research page of the Theoretical
chemistry group.
Other scientific interests of mine are for instance, magnetic properites of organic polymers, optical properties of organic chromophores, nanotechnology and nanoscience - nanotubes and fullerenes, etc. I am also interested in simulation techniques - Monte Carlo and Molecular dynamics.
My Master thesis explored the design of novel totally organic ferromagnetic materials. These are 1-D stack polymers consisting of non-alternant hydrocarbon rings (5- and 7-membered). We have calculated the ferromagnetic exchange interaction in the half-filled band of the polymer. Several of the suggested systems have shown strong ferromagnetic interactions and seem to be promising candidates for ferromagnetics. We have suggested and few heteroanalogues, including oxygen and nitrogen atoms. Some of them show good improvement of the exchange interaction's strength, which is combined with increased stability. Another line of investigation have been the influence of different factors, like symmetry of the elementary unit, symmetry of the HOMO orbital, the size of the elementary unit etc. This work was done under the supervision of Assoc. Prof. Alia Tadjer in the Faculty of Chemistry, Sofia University, Bulgaria.
