The Formation of Se2-: A New Resonance Raman Feature in the Photochemistry of Zeolite-Encapsulated Selenium

详细信息    查看全文

• 作者：Andreas Goldbach ; Lennox Iton ; Marcos Grimsditch ; and Marie-Louise Saboungi
• 刊名：Journal of the American Chemical Society
• 出版年：1996
• 出版时间：February 28, 1996
• 年：1996
• 卷：118
• 期：8
• 页码：2004 - 2007
• 全文大小：217K
• 年卷期：v.118,no.8(February 28, 1996)
• ISSN：1520-5126

文摘

This Raman spectroscopic study on selenium incorporated in Nd-Yzeolite presents new aspects of thephotochemistry of selenium. The formation of theSe₂^- radical anion has been established fromits resonance Ramanspectrum, consisting of ten almost equidistant bands between 328 and3220 cm^-1 on the low-energy side ofthe476.24-nm laser excitation line. The derived spectroscopicconstants of the electronic ground state are ₀ =328cm^-1 andx₀₀ = 0.71cm^-1. Another broad band at 260cm^-1 resembles features in the Raman spectraof amorphousselenium and selenium chain structures encapsulated in zeolites.Continuous irradiation at sufficiently high laserpower levels leads to depletion of the 260cm^-1 band and a simultaneous enhancement ofthe Se₂^- bands. Theseobservations are discussed with respect to the defect statesconventionally invoked for reversible photoinduced changesin amorphous selenium.