A carregar...
Projeto de investigação
Electron - Molecule Reactions: Compitational Study of Methods and their Applications to Radiosensitizers, Surfaces and Small Molecules
Financiador
Autores
Publicações
Sensing the ortho Positions in C6Cl6 and C6H4Cl2 from Cl2− Formation upon Molecular Reduction
Publication . Kumar, Sarvesh; Romero, José; Probst, Michael; Maihom, Thana; García, Gustavo; Limão-Vieira, Paulo; DF – Departamento de Física; CeFITec – Centro de Física e Investigação Tecnológica; MDPI - Multidisciplinary Digital Publishing Institute
The geometrical effect of chlorine atom positions in polyatomic molecules after capturing a low-energy electron is shown to be a prevalent mechanism yielding Cl2−. In this work, we investigated hexachlorobenzene reduction in electron transfer experiments to determine the role of chlorine atom positions around the aromatic ring, and compared our results with those using ortho-, meta- and para-dichlorobenzene molecules. This was achieved by combining gas-phase experiments to determine the reaction threshold by means of mass spectrometry together with quantum chemical calculations. We also observed that Cl2− formation can only occur in 1,2-C6H4Cl2, where the two closest C–Cl bonds are cleaved while the chlorine atoms are brought together within the ring framework due to excess energy dissipation. These results show that a strong coupling between electronic and C–Cl bending motion is responsible for a positional isomeric effect, where molecular recognition is a determining factor in chlorine anion formation.
Electron-impact ionization cross sections of small molecules containing Fe and Cr *
Publication . Romero, José; Limão-Vieira, Paulo; Probst, Michael; DF – Departamento de Física; CeFITec – Centro de Física e Investigação Tecnológica; IOP Publishing
We present the electron-impact ionization cross sections(EICSs) of iron and chromium hydrides, nitrides, and oxides. The motivation of this work stems from the fact that chemical sputtering from a steel surface exposed to a hot plasma can create these molecules which in turn influence the composition and energy balance of the plasma. The latter influence is quantified by the EICS which we derive by using two semi-empirical methods which can be employed in the relevant energy range of 10-1000 eV. They are important molecular properties for plasma- and materials science. We discuss the foundations of the methods and present the cross sections of the high- and low-spin states of the species in their neutral ground states and of their cations.
Unidades organizacionais
Descrição
Palavras-chave
Contribuidores
Financiadores
Entidade financiadora
Fundação para a Ciência e a Tecnologia
Programa de financiamento
Número da atribuição
PD/BD/142846/2018