Banca de DEFESA: JOSENILTON DO NASCIMENTO SOUSA

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
DISCENTE : JOSENILTON DO NASCIMENTO SOUSA
DATA : 29/08/2019
HORA: 09:00
LOCAL: Instituto de Física da Universidade Federal da Bahia
TÍTULO:

Theoretical-Experimental Study of Selection of
Photoionization Shock and Photoabsorption of
Heterocyclic Organic Molecules in
Vacuum Ultraviolet Region

PALAVRAS-CHAVES:

Photoabsorption; Photoionization; Heterocyclic molecules

PÁGINAS: 177
GRANDE ÁREA: Ciências Exatas e da Terra
ÁREA: Física
RESUMO:

nderstanding the evolutionary process of the universe, from the formation of simple molecules to more complex molecules, has been a topic widely discussed in the scientific community. In astrobiology it is believed that cyclic organic compounds may have played an important role in the evolution of life on earth, having important prebiotic functions. One way to quantify photochemical processes is by determining
of the photoabsorption shock section. Particularly, the knowledge of the absolute absorption shock section for complex polyatomic species generally permeates a certain experimental action. In this context, we performed an experimental investigation of photoabsorption and photoionization processes through the interaction of synchrotron radiation in the
vacuum ultraviolet region in heterocyclic organic molecules in the gas phase. Specifically, we are interested in studying the simplest 6- and 5-membered fundamental molecules, namely Pyridine, Pirrol, Furano and Thiophene, for their importance in understanding the synthesis of more complex cyclic species in the interstellar medium. The measures
Experimental experiments were performed at the National Synchrotron Light Laboratory, Campinas-SP, using the technique of the Dual Ionization Chamber. With this technique it was possible to measure the photoabsorption shock sections from the first ionization threshold up to 21.5 eV, and the quantum photoionization efficiency. Photoionization and decay shock sections
neutral scale were then derived from this data. In addition, a theoretical study was performed using Schwinger's Iterative Variational Method (SVIM) and the PolyScat computational package to calculate Pirrol's photoionization shock section. Additionally, the absolute partial photoionization shock (PICS) section was determined for
each fragment of Pyridine, from the product of the photoionization shock section (oi) with the respective relative productions of the different ions. The sum rule was also used to calculate the static polarization value of electric dipole for these molecules.
Comparisons are made with experimental and theoretical data available in the literature.

MEMBROS DA BANCA:
Presidente - 1194645 - FREDERICO VASCONCELOS PRUDENTE
Interno - 1878138 - LUIZ ANTONIO VIEIRA MENDES
Externo à Instituição - VICTOR MANCIR DA SILVA SANTANA - UFBA
Externo à Instituição - MILTON MASSUMI FUJIMOTO - UFPR
Externo à Instituição - ANA LUCIA FERREIRA BARROS - CEFET/RJ