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Yahiro H, Lund A, Shiotani M. Nitric oxide adsorbed on zeolites: EPR studies. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2004; 60:1267-1278. [PMID: 15134724 DOI: 10.1016/j.saa.2003.10.045] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2003] [Accepted: 10/12/2003] [Indexed: 05/24/2023]
Abstract
CW-EPR studies of NO adsorbed on sodium ion-exchanged zeolites were focused on the geometrical structure of NO monoradical and (NO)2 biradical formed on zeolites. The EPR spectrum of NO monoradical adsorbed on zeolite can be characterized by the three different g-tensor components and the resolved y-component hyperfine coupling with the 14N nucleus. Among the g-tensor components, the value of g(zz) is very sensitive to the local environment of zeolite and becomes a measure of the electrostatic field in zeolite. The temperature dependence of the g-tensor demonstrated the presence of two states of the Na-NO adduct, in rigid and rotational states. The EPR spectra of NO adsorbed on alkaline metal ion-exchanged zeolite and their temperature dependency are essentially the same as that on sodium ion-exchanged zeolite. On the other hand, for NO adsorbed on copper ion-exchanged zeolite it is known that the magnetic interaction between NO molecule and paramagnetic copper ion are observable in the spectra recorded at low temperature. The signals assigned to (NO)2 biradical were detected for EPR spectrum of NO adsorbed on Na-LTA. CW-EPR spectra as well as their theoretical calculation suggested that the two NO molecules are aligned along their N-O bond axes. A new procedure for automatical EPR simulation is described which makes it possible to analyze EPR spectrum easily. In the last part of this paper, some instances when other nitrogen oxides were used as a probe molecule to characterize the zeolite structure, chemical properties of zeolites, and dynamics of small molecules were described on the basis of selected literature data reported recently.
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Affiliation(s)
- Hidenori Yahiro
- Department of Applied Chemistry, Faculty of Engineering, Ehime University, Matsuyama 790-8577, Japan
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Ferretti AM, Barra AL, Forni L, Oliva C, Schweiger A, Ponti A. Electron Paramagnetic Resonance Spectroscopy of Iron(III)-Doped MFI Zeolite. 1. Multifrequency CW-EPR. J Phys Chem B 2004. [DOI: 10.1021/jp0370371] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- A. M. Ferretti
- Università di Milano, Dipartimento di Chimica Fisica ed Elettrochimica, via C. Golgi 19, I-20133 Milano, Italy, Centre National de la Recherche Scientifique, Laboratoire des Champs Magnétiques Intenses, F-38042 Grenoble, France, Laboratorium für Physikalische Chemie, ETH Hönggerberg, HCI, CH-8093 Zürich, Switzerland, and Consiglio Nazionale delle Ricerche, Istituto di Scienze e Tecnologie Molecolari, via C. Golgi 19, I-20133 Milano, Italy
| | - A.-L. Barra
- Università di Milano, Dipartimento di Chimica Fisica ed Elettrochimica, via C. Golgi 19, I-20133 Milano, Italy, Centre National de la Recherche Scientifique, Laboratoire des Champs Magnétiques Intenses, F-38042 Grenoble, France, Laboratorium für Physikalische Chemie, ETH Hönggerberg, HCI, CH-8093 Zürich, Switzerland, and Consiglio Nazionale delle Ricerche, Istituto di Scienze e Tecnologie Molecolari, via C. Golgi 19, I-20133 Milano, Italy
| | - L. Forni
- Università di Milano, Dipartimento di Chimica Fisica ed Elettrochimica, via C. Golgi 19, I-20133 Milano, Italy, Centre National de la Recherche Scientifique, Laboratoire des Champs Magnétiques Intenses, F-38042 Grenoble, France, Laboratorium für Physikalische Chemie, ETH Hönggerberg, HCI, CH-8093 Zürich, Switzerland, and Consiglio Nazionale delle Ricerche, Istituto di Scienze e Tecnologie Molecolari, via C. Golgi 19, I-20133 Milano, Italy
| | - C. Oliva
- Università di Milano, Dipartimento di Chimica Fisica ed Elettrochimica, via C. Golgi 19, I-20133 Milano, Italy, Centre National de la Recherche Scientifique, Laboratoire des Champs Magnétiques Intenses, F-38042 Grenoble, France, Laboratorium für Physikalische Chemie, ETH Hönggerberg, HCI, CH-8093 Zürich, Switzerland, and Consiglio Nazionale delle Ricerche, Istituto di Scienze e Tecnologie Molecolari, via C. Golgi 19, I-20133 Milano, Italy
| | - A. Schweiger
- Università di Milano, Dipartimento di Chimica Fisica ed Elettrochimica, via C. Golgi 19, I-20133 Milano, Italy, Centre National de la Recherche Scientifique, Laboratoire des Champs Magnétiques Intenses, F-38042 Grenoble, France, Laboratorium für Physikalische Chemie, ETH Hönggerberg, HCI, CH-8093 Zürich, Switzerland, and Consiglio Nazionale delle Ricerche, Istituto di Scienze e Tecnologie Molecolari, via C. Golgi 19, I-20133 Milano, Italy
| | - A. Ponti
- Università di Milano, Dipartimento di Chimica Fisica ed Elettrochimica, via C. Golgi 19, I-20133 Milano, Italy, Centre National de la Recherche Scientifique, Laboratoire des Champs Magnétiques Intenses, F-38042 Grenoble, France, Laboratorium für Physikalische Chemie, ETH Hönggerberg, HCI, CH-8093 Zürich, Switzerland, and Consiglio Nazionale delle Ricerche, Istituto di Scienze e Tecnologie Molecolari, via C. Golgi 19, I-20133 Milano, Italy
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