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Can Dynamics Be Responsible for the Complex Multipeak Infrared Spectra of NO Adsorbed to Copper(II) Sites in Zeolites?
Author(s) -
Göltl Florian,
Sautet Philippe,
Hermans Ive
Publication year - 2015
Publication title -
angewandte chemie international edition
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.831
H-Index - 550
eISSN - 1521-3773
pISSN - 1433-7851
DOI - 10.1002/anie.201501942
Subject(s) - copper , chemistry , catalysis , spectral line , adsorption , infrared , active site , infrared spectroscopy , divalent , molecule , ab initio , selective catalytic reduction , molecular dynamics , chemical physics , computational chemistry , inorganic chemistry , physics , organic chemistry , astronomy , optics
Abstract Copper‐exchanged SSZ‐13 is a very efficient material in the selective catalytic reduction of NO x using ammonia (deNO x ‐SCR) and characterizing the underlying distribution of copper sites in the material is of prime importance to understand its activity. The IR spectrum of NO adsorbed to divalent copper sites are modeled using ab initio molecular dynamics simulations. For most sites, complex multi‐peak spectra induced by the thermal motion of the cation as well as the adsorbate are found. A finite temperature spectrum for a specific catalyst was constructed, which shows excellent agreement with previously reported data. Additionally these findings allow active and inactive species in deNO x ‐SCR to be identified. To the best of our knowledge, this is the first time such complex spectra for single molecules adsorbed to single active centers have been reported in heterogeneous catalysis, and we expect similar effects to be important in a large number of systems with mobile active centers.