Oxidation effects in beryl induced by synchrotron radiation

✍ Scribed by Sigrid Griet Eeckhout; Thomas Neisius; Cristiane Castañeda

• Publisher: Elsevier Science
• Year: 2005
• Tongue: English
• Weight: 123 KB
• Volume: 229
• Category: Article
• ISSN: 0168-583X
• DOI: 10.1016/j.nimb.2004.11.001

✦ Synopsis

Successive fluorescence-yield X-ray absorption near-edge structure spectra, collected within 30 s in quick-scan mode, show the extremely fast oxidation process of iron in natural, yellow and green beryl induced by synchrotron radiation. Initially, the Fe 3+ /Fe 2+ ratio equals 0.52, which, with increasing time of exposure to the incident X-ray beam, increases to 2.03. The oxidation process starts about 5 min after exposure to the X-ray beam. From that moment on, after 30 s, the amount of ferric iron increases by $1.3%, implying that the exact amount of ferrous and ferric iron in beryl cannot precisely be determined when using the much slower, step-by-step scanning mode.