This article presents the hydrogen storage capacity of Ar
encapsulated and Li functionalized Si12C12heterofullerene using state-of-the-art Density Functional Theory (DFT) simulations. We find that the Li
atom regioselectively prefers to bind at the top of the tetragonal sites of Ar
encapsulated Si12C12 heterofullerene with a maximum binding energy of
2.02 eV. Our study reveals that...
To study the rate of elementary reactions and their dynamics, we use Potential Energy Surfaces, being useful to compute state-to-state rate constants. The usual approach to study such system is to make use of all the system's available rate constants and build a system of master equations. This procedure assumes that reactants are in thermal equilibrium. Studies seem to indicate that the...
A computational protocol is proposed in this talk for use in discovering reaction mechanisms. The method does not rely on either chemical intuition or assumed a priori mechanisms, working in a fully automated fashion.
The pipeline consists of three steps:
1. Exploration of reaction mechanisms through Molecular Dynamics simulations or chemical knowledge-based algorithms.
2. Use of Graph...
Shale formations are recognized as an essential source of unconventional hydrocarbons, with kerogen, the embedded carbonaceous porous material, being the dominant source of valuable organic components. The unique nanostructure of kerogen, coupled with its inherent complexity, presents a significant challenge to unraveling the behavior of confined fluids and interactions within shale...
Computational description of light emission processes in organic TADF blue emitters
Georgia Ivanova, Simona Djumayska, Neda Todorova, Anela Ivanova
Faculty of Chemistry and Pharmacy, Sofia University, 1 James Bourchier blvd., Sofia, Bulgaria
E-mail: aivanova@chem.uni-sofia.bg
Organic light emitting diodes (OLEDs) are among the optoelectronic devices for which research is employed...
Understanding how complex organic molecules are formed in the harsh environment of the interstellar medium has long presented a significant puzzle to scientists. In molecular clouds, irradiation of ice plays a crucial role in producing complex organic molecules. In this work, we present ab-initio molecular dynamics (AIMD) simulations to model reaction taking place on ice with astronomical...
Given the technological needs for molecular systems with tailored photophysical properties there are on-going efforts to develop cost-effective but reliable computational protocols supporting the design of efficient multiphoton absorbers.
For example, it was demonstrated that two-photon absorption exhibits large application potential, including: photodynamic therapy, 3D microfabrication, or...
The design of nanoscale information storage devices based on molecular magnets requires the preparation of materials with well-designed spin-phonon interactions such that magnetic memory persists at ambient temperatures. Understanding the fine details of spin-phonon coupling is thus crucial in designing new materials for this task. Of crucial importance for molecular spin dynamics is the...
The study of photoexcitations in molecular aggregates faces the twofold problem of the increased computational cost associated with excited states and the complexity of the interactions among the constituent monomers. A mechanistic investigation of these processes requires the analysis of the intermolecular interactions, the effect of the environment, and 3D arrangements or crystal packing on...
Reliable manipulation of the interface between 2D nanomaterials and biomolecules represents a current frontier in nanoscience. The ability to resolve the molecular-level structures of these bio-interfaces would provide a fundamental data set that is needed to enable systematic and knowledge-based progress in this area. These structures are challenging to obtain via experiment alone, and...
MReaDy (Multiprocess Reaction Dynamics program) is a program for studying reactive dynamic systems using a global potential energy surface (gPES)[1].
Potential Energy Surfaces (PES), based on ab initio calculations, is a
powerful tool to study the rate of elementary reactions and their dynamics. It is useful to compute state-to-state rate constants. In a more
complex mechanism, we will be...
In this work, we study the deactivation pathways that take place after the UV excitation to the excited state manifold of coronene and circumcoronene, small moeities used as simplified models for graphene quantum dots, nanoflakes and poliaromatic hydrocarbons (PAHs)[1-3]. We use the wavepacket method ML-MCTDH[4] to study the time evolution of the states as well as their lifetimes.
The...
All widely used semi-empirical quantum chemical methods like PM6, DFTB, or
GFN-xTB are formulated in a (almost) minimal basis set of atomic
orbitals, which limits the achievable accuracy for many important
chemical properties. Recently, we proposed a new special purpose tight-binding (TB) electronic Hamiltonian termed PTB$^{[1]}$ which is expressed in an accurate polarized valence...
The lithium chemistry has received a great attention in recent years due to the importance that LiH molecules and its ionic variants can have in the primordial universe1,2. The reaction LiH + H → Li + H2 is considered to contribute to LiH depletion, while the hydrogen-exchange reaction LiH + H → LiH + H leads to the retention of LiH in this process.
In this work we report our recent studies...
The polar Diels-Alder (P-DA) reactions between cyclopentadiene and the cyanoethylene series, experimentally studied by Sauer, have been studied[1] within the Molecular Electron Density Theory (MEDT)[2], which establishes that changes in electron density, but not molecular orbital interactions, are responsible for organic chemical reactivity. Accordingly, any study of reactivity within the...
Hydrogen bonds are omnipresent in biological and supramolecular chemistry. Nevertheless, they are still mostly represented in an oversimplified manner (positively charged hydrogen attracts close-by negatively charged heteroatom) which is easy to use but often fails to explain or even qualitatively reproduce experimental findings. In my lecture, I present a state-of-the art physical model,...
