The squaric acid aggregate in mordenite investigated by Raman spectroscopy |
| |
| Authors: | Lopes J G de Oliveira L F Santos P S |
| |
| Affiliation: | 1. Departamento de Quı́mica Fundamental, Instituto de Quı́mica da Universidade de São Paulo, 05508-900 São Paulo, SP, Brazil;2. Departamento de Quı́mica, Instituto de Ciências Exatas da Universidade Federal de Juiz de Fora, Minas Gerais, Brazil;1. School of Nutrition and Food Sciences, Louisiana State University AgCenter, Baton Rouge, LA, 70803, USA;2. Department of Agricultural and Extension Education & Evaluation, Louisiana State University AgCenter, Baton Rouge, LA, 70803, USA;3. School of Animal Sciences, Louisiana State University AgCenter, Baton Rouge, LA, 70803, USA;1. Department of Chemistry, Syracuse University, Syracuse, NY 13244, United States;2. Fakultät für Chemie der Universität, Postfach 100131, D-33501 Bielefeld, Germany;1. Department of Inorganic and Analytical Chemistry, University of Szeged, Dóm tér 7, H-6720 Szeged, Hungary;2. Institute for Energy Security and Environmental Safety, Centre for Energy Research, Hungarian Academy of Sciences, Konkoly-Thege Miklós út 29-33, H-1121 Budapest, Hungary;3. Department of Organic Chemistry and Technology, Budapest University of Technology and Economics, Szent Gellért tér 4, H-1111 Budapest, Hungary |
| |
| Abstract: | A more detailed investigation of the squaric acid aggregate within mordenite was undertaken with the use of Raman spectroscopy. The previous reported investigation was limited to the carbonyl stretching region in the IR. In the present work the entire region from 500 to 2000 cm(-1) was investigated, revealing rather substantial vibrational shifts of the oxocarbon ring modes in the aggregate. Comparison of such shifts with those observed for the squaric acid (H2Sq)/4,4'-bipyridine (Bipy) charge transfer (CT) complex reveals that the interaction is much stronger in the aggregate, a clear effect of the restrict geometry. On the other hand, the shifts observed for the CO stretching modes are rather modest. The comparison of the ring modes present in the Raman spectra of squaric acid, potassium hydrogen squarate, potassium squarate, H2Sq/Bipy and squaric acid aggregate in mordenite strongly suggests that in the latter hydrogen bonded species are present. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect PubMed 等数据库收录！ |
|
