Electron paramagnetic resonance evidence for the formation of dioxosulfate(1-) ion on magnesium oxide

Abstract

Formation of 820 on Magnesium Oxide 635 long axes with little if any effect on the crystal stabilization energy.Since the direction of the transition dipoles is not influenced by the order-disorder phenomenon, the crystal structure determined by Neely and Anex would be expected, at least to a first approximation, to have similar optical properties to the crystal structure described here. Nevertheless it should be noted in future that two crystal forms of BDP may be possible, and that it may be important to distinguish between them in order to understand in detail the optical properties of these crystals. ment Award (GM70585) from the Institute of General Medical Sciences. Supplementary Material Available: Table IV contains structure factor tables (10 pages). Ordering information is given on any current masthead page. References and Notes(1) Alfred P.

EPR Characterization and Reactivity of Surface-Localized Inorganic Radicals and Radical Ions

“…The chemical process is based on the reaction of H 2 S and SO 2 producing water and S 2 . The diatomic species then reacts with a surface oxygen ion, yielding S 2 O − and releasing an electron: 4 H 2 S ( ads ) + 2 SO 2 ( ads ) → 4 H 2 O ( ads ) + 3 S 2 ( ads ) S 2 ( ads ) + O ( surf ) 2 − → S 2 O ( surf ) − + e − …”

“…The chemical process is based on the reaction of H 2 S and SO 2 producing water and S 2 . The diatomic species then reacts with a surface oxygen ion, yielding S 2 Oand releasing an electron: 205 The S 3 radical ion 206 originates by reaction of elemental sulfur with partially hydroxylated MgO at 400 K. A sharp axial spectrum is observed using nonenriched sulfur whose principal g values are g ⊥ ) 2.043 and g | ) 2.004. Around these features, a complex hyperfine structure (with primary, secondary, and tertiary splittings) can be analyzed on the basis of two distinct coupling constants (Figure 28).…”

EPR study of electron trapping on partially hydroxylated alkali-earth oxides occurring during SO2 disproportionation

“…whose g tensor is only slightly affected by the surrounding crystal field [24]. For this reason the signal does not show any relevant difference between the two oxides surfaces.…”

SO2 reactivity on the MgO and CaO surfaces: A CW-EPR study of oxo-sulphur radical anions

“…In general, such a similar charge transfer is difficult on oxide surfaces due to the low electron density on the metal cations. [19][20][21][22][23] Lunsford, years ago, demonstrated that sulphur dioxide reacts with MgO at room temperature to form sulphite and sulphate complexes [24][25][26] . At higher temperatures, infrared evidence suggests that sulphite ions react with molecular oxygen to form bidentate sulphate complexes in addition to strongly bound SO 3 .…”

“…•species was not introduced in this simulation as present in very low concentration. The spectrum is composed by the superimposition of two signals with a quasi axial g tensor and has the structure expected for 19 electrons three-atomic radicals like O 3•or ClO 2• whose g tensor is only slightly affected by the surrounding crystal field24 . Figure5reports the spectrum experimental trace (a) and the simulation (b) observed after SO 2 adsorption on CaO/(H + )(e -) and recorded at 8mW microwave power.…”