| 1 | Author
| Peter Morys, Sabine Schmerbeck | Requires cookie* | | Title
| Über die Photolumineszenz von Oberflächenverbindungen des Molybdäns auf Silicagel On the Photoluminescence of Molybdenum Surface Compounds on Silicagel Supports  | | | Abstract
| The UV induced photoluminescence (PL) of activated and reduced surface molybdenum com-pounds on silica gel has been studied at various concentrations of the products under He and Ar and at various temperatures from R.T. to 10 K. With the activated molybdenum(VI) compounds, four different types of broad band emissions were observed and assigned to definite surface species of Mo(VI): A blue PL occurring mainly at T > -90 °C, two "white" emissions with different spectral excitation regions and Stokes shifts appearing very strongly under He or vacuum below T < —90 °C and a yellow PL occurring with the products under Ar, N 2 or C0 2 instead of the "white" ones. While the blue PL was ascribed to an octahedrally coordinated surface species (Moc 1), the two "white" emissions were attributed to two tetrahedrally coordinated surface species, the first one (MoX 1) being monomeric and bonded directly to the surface, the second one (Mo^ 1) being bonded to a polymolybdate cluster and excited via that cluster; the yellow PL was postulated to originate from a MOB 1 —Ar Van der Waals complex. At 10 K the "white" PL of the polymeric MOB 1 species showed a faint vibronic fine structure; the emission time constant was measured to be 5 ms. With the reduced compounds, only one PL was observed attributable to the monomeric MoX 1 species. Hence this species was concluded to be the only one not or not completely being reducible. | | |
Reference
| Z. Naturforsch. 42b, 756—763 (1987); eingegangen am 16. Januar 1987 | | |
Published
| 1987 | | |
Keywords
| Luminescence, Surface Compounds, Molybdenum Compounds | | |
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| default:Reihe_B/42/ZNB-1987-42b-0756.pdf | | | Identifier
| ZNB-1987-42b-0756 | | | Volume
| 42 | |
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