Optical seminar | 21 May 2021

Rashid Valiev
Tomsk State University, University of Helsinki
Theoretical models for fast assessment of photophysical and photochemical characteristics of molecules by quantum chemical methods

The photophysical and photochemical properties of molecules are determined by the quantum yields of certain molecular processes, which immediately depend on the energy and lifetime of the electronic states of the molecules. For example, the knowledge of fluorescence and phosphorescence quantum yields of molecules is important in the design of organic light-emitting diodes; efficiency of singlet-to-triplet transition is necessary in the photodynamic cancer therapy, where effective oxidizing agents are created to kill cancer cells. To study the photodissociation dynamics of molecules in astrophysics, it is necessary to calculate the lifetime of molecules in excited electronic states. In atmospheric chemistry, the formation of hazardous aerosol particles in the troposphere is completely determined by the lifetime of intermediate products in excited electronic states. Photophysical properties are important for increasing the efficiency of dye lasers and charge transfer and separation in solar cells.

Within my talking, I tell about quantum chemistry for photophysical and photochemical applications: from material science to atmospheric research. Also, I describe the relationship between the aromaticity and the photophsyical properties of macrocyclic molecules.

1. Glib V. Baryshnikov, Rashid R. Valiev, Artem V. Kuklin, Dage Sundholm, Hans Ågren. Cyclo[18]carbon: Insight into Electronic Structure, Aromaticity, and Surface Coupling. J. Phys. Chem. Lett. 2019, 10, 6701-6705.

2. R. R. Valiev et al: The blue vibronically resolved electroluminescence of azatrioxa[8]circulene, Chem. Phys. Lett. 2019, 732 , 136667.

3. R. R. Valiev et al: First-principles calculations of anharmonic and deuteration effects on the photophysical properties of polyacenes and porphyrinoids, PCCP, 2020, 22, 22314.

4. R. Valiev et al: First-principles method for calculating the rate constants of internal-conversion and intersystem-crossing transitions. PCCP, 2018, 20, 6121.

5. R. R. Valiev et al: Fast estimation of the internal conversion rate constant in photophysical applications, PCCP, 2021, 23, 6344 – 6348.