CASP Lecture

Quantum Chemistry of Quantum Dots

Sergei Tretiak

Theoretical Division, CNLS, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA

Wednesday, April 21st, 10am

Chemistry Division Auditorium, TA-46, Bld. 535, Rm. 103

Abstract


Over the years, electronic structure calculations, such as density functional theory (DFT), transformed theoretical chemistry and materials science by creating a new capacity to describe the electronic structure and complex dynamics in molecules with hundreds of atoms. This talk will overview applications of modern quantum chemical methodologies to electronic structure of semiconductor nanocrystals. I will start with a brief introduction to the wavefunction and DFT methodologies and their extensions to the excited state calculations. Then I will overview several recent literature reports on quantum chemical studies of quantum dots (QDs) and will discuss possible advantages and sources of errors in these applications. In the second part of my talk I will analyze our benchmark of several computational methods versus high level ab initio techniques for the minimal CdSe clusters to assess an accuracy of different theories. Finally I will present our studies on the surface ligands effects on the QDs electronic structure, where we observe strong surface-ligand interactions leading to formation of hybridized states. This potentially opens new relaxation channels for high energy photoexcitations.