https://repositorio.ufba.br/handle/ri/12801
Tipo: | Artigo de Periódico |
Título: | Site-selective photofragmentation of chlorinated polymeric films observed around the chlorine K-edge |
Título(s) alternativo(s): | Chemical Physics |
Autor(es): | Arantes, C. Mendes, L. A. V. Pinho, R. R. Ferreira, M. Souza, Gerardo Gerson Bezerra de Rocha, A. B. Rocco, M. L. M. |
Autor(es): | Arantes, C. Mendes, L. A. V. Pinho, R. R. Ferreira, M. Souza, Gerardo Gerson Bezerra de Rocha, A. B. Rocco, M. L. M. |
Abstract: | Photon stimulated ion desorption (PSID) and Near-edge X-ray absorption fine structure (NEXAFS) studies have been performed on poly(vinyl chloride) (PVC) and poly(vinyl dichloride) (PVDC) around the chlorine 1s-edge. Experiments were performed using a synchrotron source operating in the single-bunch mode and a time-of-flight mass spectrometry for ion analysis. Cl+ ion yields, as a function of the photon energy, reproduce the photoabsorption spectrum, showing significant increase at the 1s-resonance. Edge-jump ratios, defined as the ratio between edge-jumps (intensity ratio of the yields between above and below the absorption edge) of two different transitions, for Cl+ ion yields were much higher than the equivalent electron yields, indicating site-selectivity in C–Cl bond breaking for both polymers, as a result of efficient spectator Auger decay. The expected isotope ratio of 3:1 for chlorine was measured for PVC. The interpretation of the NEXAFS spectrum was assisted by quantum mechanical calculations at a multireference perturbation theory level. |
Palavras-chave: | Fotofragmentação Raios X Cloreto de vinila Vinil dicloreto |
Editora / Evento / Instituição: | Chemical Physics |
URI: | http://www.repositorio.ufba.br/ri/handle/ri/12801 |
Data do documento: | 2013 |
Aparece nas coleções: | Artigo Publicado em Periódico (FIS) |
Arquivo | Descrição | Tamanho | Formato | |
---|---|---|---|---|
7777777777777777.pdf | 394,81 kB | Adobe PDF | Visualizar/Abrir |
Os itens no repositório estão protegidos por copyright, com todos os direitos reservados, salvo quando é indicado o contrário.