Detailed simulations are reported for the dynamics of electrons and nuclei during the cis to trans photoisomerization of stilbene. Our method, which employs a semiclassical description of both the nuclear motion and the radiation field, is described in the text. After excitation of electrons from the highest occupied molecular orbital ~HOMO! to the lowest unoccupied molecular orbital ~LUMO! by ...

Dynamic behaviors of chemical concepts in density functional theory such as frontier orbitals (HOMO/LUMO), chemical potential, hardness, and electrophilicity index have been investigated in this work in the context of Bohn-Oppenheimer quantum molecular dynamics in association with molecular conformation changes. Exemplary molecular systems like CH5 , Cl (H2O)30 and Ca 2+ (H2O)15 are studied at ...

Simulations of the photoconversion of 4a,4b-dihydrophenanthrene (DHP) to stilbene, using semiclassical electron-radiation-ion dynamics, are reported. The carbon single bond connecting the phenyl rings breaks approximately 200 fs after the laser pulse is turned off. In the results shown here, the excited cis-stilbene molecule then further isomerizes to the trans conformation after about 1 ps. Ea...

Detailed simulations are reported for the coupled dynamics of electrons and nuclei in the isomerization reaction of cis-stilbene stimulated by laser excitation. The results demonstrate that, in addition to the traditional vinyl and vinyl– phenyl torsions, the HCCH torsional coordinate of the vinyl group also makes a significant contribution to the HOMO and LUMO couplings that yield nonradiative...

In this paper and in order to guide the synthesis of novels materials with low band gaps, Theoretical study by using DFT method on six conjugated compound containing based on thiadiazolothienopyazine is reported. Different electron side groups were introduced to investigate their effects on the electronic structure. The theoretical knowledge of the HOMO and LUMO energy levels of the components ...

The extended SSH model and Bogoliubov-de Gennes(BdeG) formalism are applied to investigate the electronic properties and stable lattice configurations of C36. We focus the problem on the molecule’s unusual D6h symmetry. The electronic part of the Hamiltonian without Coulomb interaction is solved analytically. We find that the gap between HOMO and LUMO is small due to the long distance hopping b...

We report experimental measurements and analysis of HOMO-LUMO transition photoluminescence and photoinduced bleaching magnitude and decay kinetics in lead sulfide quantum dots in glass. We find that the radiative lifetime is independent of temperature from 77K to 500K. The lifetime of the HOMO-LUMO state decreases dramatically for T>300K, indicating thermally activated nonradiative recombinatio...

a novel pyridine-2,6-dicarboxylic acid mixed ligands complex of formula [co(no3)2].6h2o has been obtained by the reaction of pyridine-2,6-dicarboxylic acid with cobalt nitrate and 1,10-phenanthroline on heating in water. the structures of [co(pydc)(phen)(h2o)](pydch2).4h2o receptors, and their complexes were optimized using dft method at the b3lyp/3-21g** level. the highest occupied molecular o...

in this paper, the structural properties of c20 and c12b8 fullerene interacting with glycine based onthree active sites of glycine and one c atom or one b atom in c12b8 were analyzed through thedensity functional theory. it was found out that the binding of glycine to c12b8 generated a complex.our results were extremely relevant in order to identify the potential applications of functionalizedc...