Banca de QUALIFICAÇÃO: ANTENOR JORGE PARNAÍBA DA SILVA

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : ANTENOR JORGE PARNAÍBA DA SILVA
DATE: 22/08/2024
TIME: 14:00
LOCAL: Ambiente virtural Google Meet
TITLE:

Electronic Structure Modeling, Charge Population Analysis and Electron Transfer Efficiency Estimates Using the Green's Function Formalism in Bistable Chemical Compound Systems

KEY WORDS:

Bistable configurations; Cellular automata of molecular quantum dots; Creutz-Taube analog ions; Charge population analysis

PAGES: 136
BIG AREA: Ciências Exatas e da Terra
AREA: Química
SUBÁREA: Físico-Química
SPECIALTY: Química Teórica
SUMMARY:

The purpose of this study is to model electronic structures and the electron transfer potential of bistable chemical compounds that can be used in molecular quantum dot cellular automata. In the MQCA model, the main requirement for a molecular system to encode binary information is that the candidate molecule must support bistable charge configurations that can be exchanged by Coulomb interactions. In order to establish which compounds and which chemical phenomena can interfere in charge transfer processes by Coulomb interaction, four types of chemical phenomena involving charge transfer were chosen to model potential systems that can be used in cellular automata: formation of hydrogen complexes, solvent effect on charge transfer in nitroaniline molecules, electron transfer induced by an external magnetic field in organo-diboryl monoradical anions, and photoinduced electron transfer in Creutz-Taube-like ions. To estimate the charge transfer efficiency, the formalism of Green's functions and charge population analyses were used. Preliminarily, among the main results obtained, it was observed that the correlation between the charge transfer variables is more accurate at larger intermolecular distances, with emphasis on the CHELPG and Mülliken charge population methods. It was initially found that hydrogen bonds between solute and solvent tend to interfere destructively in the electron transfer to nitroaniline. In the study of electron transfer processes induced by a magnetic field, it was observed that the electron transfer process is more stable the greater the shielding of the first-sphere ligands of the charge localizing center. Regarding the Creutz-Taube analog ions, the main focus of the study, the initial results demonstrate qualitatively good levels of correlation with experimental data, but require further refinement, mainly in the issue of spin contamination in the wave function of the ions, where it was noted that spin contamination is more pronounced in structures involving iron in the metal centers of the ions. Preliminary results of this study indicate that electronic structure modeling and charge transfer analysis for bistable compounds are promising using the Green's function formalism and charge population analysis.

COMMITTEE MEMBERS:
Presidente - ***.999.014-** - JULIANA ANGEIRAS BATISTA DA SILVA - UFPE
Interno - WAGNER EDUARDO DA SILVA
Externo à Instituição - AUGUSTO CESAR LIMA MOREIRA
Externo à Instituição - RENALDO TENORIO DE MOURA