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Experimental and Theoretical Study on the Gas-Phase Reactions of Germyl Radicals with NF3: Homolytic Substitution at the Nitrogen Atom vs Fluorine Abstraction.

ABSTRACT: In this paper, we report on the unexplored reaction mechanisms of bimolecular homolytic substitution (SH2) between GeH3 radicals and the nitrogen atom of NF3. The SH2 reactions are studied both experimentally and theoretically with ab initio and density functional theory (DFT) calculations. The experimental results of X-ray irradiation of mixtures of GeH4 and NF3 show the formation of GeH3-NF2 and GeH3-F. The trend of product yields as a function of the increase in GeH4 partial pressure in the irradiated mixtures evidences the predominant role of GeH3 radicals. Particularly, the SH2 mechanism can be hypothesized for the reaction between GeH3 radicals and NF3 molecules leading to GeH3-NF2. This mechanism is further confirmed by the increase in GeH3-NF2 yield observed if O2 is added, as a radical scavenger, to the reaction mixture. In agreement with the experimental data, from the calculations performed at the CCSD(T) and G3B3 levels of theory, we observe that the GeH3-NF2 product actually occurs from a bimolecular homolytic substitution by the GeH3 radical, which attacks the N atom of NF3, and this reaction is in competition with the fluorine abstraction reaction leading to GeH3F, even if other mechanisms may be involved in the formation of this product.

SUBMITTER: Antoniotti P

PROVIDER: S-EPMC7081285 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature

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Experimental and Theoretical Study on the Gas-Phase Reactions of Germyl Radicals with NF3: Homolytic Substitution at the Nitrogen Atom vs Fluorine Abstraction.

Antoniotti Paola P Benzi Paola P Marabello Domenica D Rosso Daniele D

ACS omega 20200303 10

In this paper, we report on the unexplored reaction mechanisms of bimolecular homolytic substitution (SH2) between GeH3 radicals and the nitrogen atom of NF3. The SH2 reactions are studied both experimentally and theoretically with ab initio and density functional theory (DFT) calculations. The experimental results of X-ray irradiation of mixtures of GeH4 and NF3 show the formation of GeH3-NF2 and GeH3</ ...[more]

PMID: 32201776

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Dataset Information

Experimental and Theoretical Study on the Gas-Phase Reactions of Germyl Radicals with NF3: Homolytic Substitution at the Nitrogen Atom vs Fluorine Abstraction.

Publications

Experimental and Theoretical Study on the Gas-Phase Reactions of Germyl Radicals with NF<sub>3</sub>: Homolytic Substitution at the Nitrogen Atom vs Fluorine Abstraction.

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