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Infrared spectroscopic study of the bending modes of the Brønsted acidic sites in deuterated zeolites

✍ Scribed by W.P.J.H. Jacobs; J.H.M.C. van Wolput; R.A. van Santen

Publisher
Elsevier Science
Year
1993
Tongue
English
Weight
425 KB
Volume
210
Category
Article
ISSN
0009-2614

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✦ Synopsis

Deuteration of Bronsted acidic sites in zeolites gives observable infrared in-plane O-D bending modes. For zeolite Y and ZK-5, a maximum near 870 cm-' with a shoulder near 890 cm-' is observed. These signals arc related to, respectively, the highfrequency and the low-frequency stretching modes. Mordenite, zeolite b and ZSM-5 possess a single mode near 890 cm-'. The zeolite structure type and composition influences the position of the modes strongly. A large anharmonicity parameter, x$' ( -80 cm-'), is found due to Fermi resonance with the zeolite lattice modes.

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