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Updated: Apr 21, 2026
08:26
Synthesis of Zeolites Using the ADOR Assembly-Disassembly-Organization-Reassembly Route
Published on: April 3, 2016
13.9K
Mononuclear iridium dinitrogen complexes bonded to zeolite HY
Dong Yang1, Mingyang Chen, Claudia Martinez-Macias
1Department of Chemical Engineering & Materials Science, University of California, Davis, One Shields Ave, Davis, CA 95616 (USA).
Chemistry (Weinheim an Der Bergstrasse, Germany)
|November 11, 2014
Summary
Iridium dinitrogen complexes form on dealuminated HY zeolite. Computational models accurately predict vibrational frequencies, aiding understanding of these supported catalysts.
Area of Science:
- Heterogeneous catalysis
- Inorganic chemistry
- Materials science
Background:
- Zeolites are versatile solid acids and supports for metal catalysts.
- Dealuminated HY zeolites offer tunable properties for catalytic applications.
- Iridium complexes are of interest for various catalytic transformations.
Purpose of the Study:
- To investigate the adsorption and formation of iridium dinitrogen complexes on dealuminated HY zeolite.
- To characterize the supported iridium species under different gas atmospheres.
- To computationally validate experimental observations of these catalytic systems.
Main Methods:
- Infrared spectroscopy using isotopically labeled N2.
- Exposure of zeolite-supported iridium complexes to various flowing gases (N2, H2, CO).
- Density functional theory (DFT) calculations for structural and vibrational analysis.
Main Results:
- Formation of four distinct iridium dinitrogen species: Ir(N2), Ir(N2)(N2), Ir(C2H5)(N2), and Ir(H)(N2).
- Ir(N2) identified as the predominant species in the presence of N2 between 273-373 K.
- Stable iridium hydride complexes formed in the presence of H2.
- DFT calculations showed good agreement with experimental vibrational frequencies.
Conclusions:
- The study elucidates the behavior of iridium complexes on dealuminated HY zeolite under N2 and other gas environments.
- Computational modeling, particularly DFT, is a reliable tool for understanding the vibrational properties of these supported complexes.
- The findings contribute to the design and optimization of supported iridium catalysts.
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