Reaction between ethylene and O– ions on the surface of magnesium oxide

Abstract

Interaction between ethylene and O^– centres on magnesium oxide surfaces gives a radical having a nearly isotropic hyperfine coupling to two equivalent hydrogen atoms (58 G), a very weak coupling to a single proton, and strong coupling to ¹³C which indicates nearly unit spin-density in a 2p orbital on a single carbon atom. These results agree with expectation for H₂CĊ^– anions, isoelectronic with the relatively stable H₂CN radical in every respect. We suggest that after initial abstraction to give H₂CĊH radicals (not detected), ionization of the acidic acetylenic type proton occurs but this remains hydrogen-bonded to the radical anion: H₂CĊ^–—HO^–.

In contrast, reaction of ethylene oxide with F⁺_s centres on the surface gave H₂Ċ—CH₂O^– radicals.