EPR Of the SeO43-, SeO3-, SeO2- and NH3+ radicals in ultraviolet-irradiated crystals of ammonium compounds

Yu Jiang-Tsu Yu, Wu Ching-Jiun Wu, Lou Ssu-Hao Lou

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2 Citations (Scopus)


Oxyradicals of selenium, such as the SeO43-, SeO4-, SeO3- and SeO2- are conventionally produced via γ- or X-irradiation. The same is also true of the NH3+ radical. We report for the first time EPR observations of these radicals produced by ultraviolet (u.v.)-irradiation in some ammonium compounds. We have investigated u.v.-irradiated crystals of (NH4)2SO4, LiNH4SO4, (NH4)3H(SeO4)2 and NH4H2PO4. The NH3+ radical has been detected by EPR in u.v.-irradiated (NH4)2SO4 and LiNH4SO4 crystals. The NH3+ radical is produced at the first stage of the u.v. photo-dissociation of the NH4+ ion in solids. The oxyradicals of selenium detected by EPR in some ammonium compounds can be regarded as the product of an u.v. photo-redox reaction between the NH4+ ion and the SeO42- ion.

Original languageEnglish
Pages (from-to)1015-1021
Number of pages7
JournalJournal of Physics and Chemistry of Solids
Issue number9
Publication statusPublished - 1993 Sep
Externally publishedYes


  • EPR
  • radical ions
  • u.v.-irradiation

ASJC Scopus subject areas

  • Chemistry(all)
  • Materials Science(all)
  • Condensed Matter Physics


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