# EPR and DFT study of the ethylene reaction with O− radicals on the surface of nanocrystalline MgO

EPR and DFT study of the ethylene reaction with O− radicals on the surface of nanocrystalline MgO Different radical forms of oxygen (O−, O 2 − and O 3 − ) on the surface of nanocrystalline MgO are well known. It was earlier demonstrated that EPR-silent species with properties very similar to those of O− radicals exist on the surface of magnesium oxide in addition to the O− radicals observed by EPR. In this study we characterized the reactivity of these two types of O− radicals in reaction with ethylene. It was demonstrated that this reaction yields different products for observable and unobservable O− radicals. Conventional $${\text{O}}_{{3{\text{C}}}}^{ - }$$ O 3 C - radicals generated by MgO illumination with UV light at room temperature in the presence of oxygen initiate hydrogen atom abstraction from ethylene to form secondary radicals H2C=C− with hyperfine splitting A 1 = 59 G, A 2 = 6 G. The $${\text{O}}_{{4{\text{C}}}}^{ - }$$ O 4 C - radicals not observed directly by EPR were synthesized by MgO illumination in the presence of oxygen at 163 K followed by evacuation at 203 K. They were shown to react with ethylene to form an addition product with two groups of two equivalent protons with isotropic hyperfine constants A 1 = 38 G and A 2 = 23 G. Such radicals were obtained for the first time by reaction of O− radicals with ethylene on the MgO surface. Their concentration was approximately equal to the concentration of [ $${\text{O}}_{{4{\text{C}}}}^{ - }$$ O 4 C - ·O2] complexes observed by EPR before the oxygen desorption. The structures of both radicals were simulated by DFT, and a good match between the experimental and computational results was obtained. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Research on Chemical Intermediates Springer Journals

# EPR and DFT study of the ethylene reaction with O− radicals on the surface of nanocrystalline MgO

, Volume 43 (2) – Aug 12, 2016
15 pages

Publisher
Springer Netherlands
Subject
Chemistry; Catalysis; Physical Chemistry; Inorganic Chemistry
ISSN
0922-6168
eISSN
1568-5675
D.O.I.
10.1007/s11164-016-2682-9
Publisher site
See Article on Publisher Site

### Abstract

Different radical forms of oxygen (O−, O 2 − and O 3 − ) on the surface of nanocrystalline MgO are well known. It was earlier demonstrated that EPR-silent species with properties very similar to those of O− radicals exist on the surface of magnesium oxide in addition to the O− radicals observed by EPR. In this study we characterized the reactivity of these two types of O− radicals in reaction with ethylene. It was demonstrated that this reaction yields different products for observable and unobservable O− radicals. Conventional $${\text{O}}_{{3{\text{C}}}}^{ - }$$ O 3 C - radicals generated by MgO illumination with UV light at room temperature in the presence of oxygen initiate hydrogen atom abstraction from ethylene to form secondary radicals H2C=C− with hyperfine splitting A 1 = 59 G, A 2 = 6 G. The $${\text{O}}_{{4{\text{C}}}}^{ - }$$ O 4 C - radicals not observed directly by EPR were synthesized by MgO illumination in the presence of oxygen at 163 K followed by evacuation at 203 K. They were shown to react with ethylene to form an addition product with two groups of two equivalent protons with isotropic hyperfine constants A 1 = 38 G and A 2 = 23 G. Such radicals were obtained for the first time by reaction of O− radicals with ethylene on the MgO surface. Their concentration was approximately equal to the concentration of [ $${\text{O}}_{{4{\text{C}}}}^{ - }$$ O 4 C - ·O2] complexes observed by EPR before the oxygen desorption. The structures of both radicals were simulated by DFT, and a good match between the experimental and computational results was obtained.

### Journal

Research on Chemical IntermediatesSpringer Journals

Published: Aug 12, 2016

## You’re reading a free preview. Subscribe to read the entire article.

### DeepDyve is your personal research library

It’s your single place to instantly
that matters to you.

over 18 million articles from more than
15,000 peer-reviewed journals.

All for just $49/month ### Explore the DeepDyve Library ### Search Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly ### Organize Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place. ### Access Get unlimited, online access to over 18 million full-text articles from more than 15,000 scientific journals. ### Your journals are on DeepDyve Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more. All the latest content is available, no embargo periods. DeepDyve ### Freelancer DeepDyve ### Pro Price FREE$49/month
\$360/year

Save searches from
PubMed

Create lists to

Export lists, citations