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Chromium Environment within Cr-Doped Silico-Aluminophosphate Molecular Sieves from Spin Density Studies.

ABSTRACT: X-/Q-band electron paramagnetic resonance (EPR) and hyperfine sublevel correlation (HYSCORE) spectroscopies have been employed, in conjunction with density functional theory (DFT) modeling, to determine the location of Cr⁵⁺ions in SAPO-5 zeotype materials. The interaction of the unpaired electron of the paramagnetic Cr⁵⁺ species with ²⁷Al could be resolved, allowing for the first detailed structural analysis of Cr⁵⁺ paramagnetic ions in SAPO materials. The interpretation of the experimental results is corroborated by DFT modeling, which affords a microscopic description of the system investigated. The EPR-active species is found to be consistent with isolated Cr⁵⁺ species isomorphously substituted in the framework at P⁵⁺ sites.

SUBMITTER: Liao YK

PROVIDER: S-EPMC8162410 | biostudies-literature | 2021 Apr

REPOSITORIES: biostudies-literature

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Chromium Environment within Cr-Doped Silico-Aluminophosphate Molecular Sieves from Spin Density Studies.

Liao Yu-Kai YK Bruzzese Paolo Cleto PC Hartmann Martin M Pöppl Andreas A Chiesa Mario M

The journal of physical chemistry. C, Nanomaterials and interfaces 20210407 15

X-/Q-band electron paramagnetic resonance (EPR) and hyperfine sublevel correlation (HYSCORE) spectroscopies have been employed, in conjunction with density functional theory (DFT) modeling, to determine the location of Cr5+ions in SAPO-5 zeotype materials. The interaction of the unpaired electron of the paramagnetic Cr5+ species with 27Al could be resolved, allowing for the first detailed structural analysis of Cr5+ paramagnetic ions in SAPO materials. ...[more]

PMID: 34084260

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