Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Analytical Chemistry and Spectroscopy  (1)
Material
Years
Keywords
  • 1
    Electronic Resource
    Electronic Resource
    Chichester [u.a.] : Wiley-Blackwell
    Journal of Raman Spectroscopy 26 (1995), S. 57-62 
    ISSN: 0377-0486
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The Raman microprobe spectra of natural brookite crystals from Switzerland and Brazil and a synthetic brookite powder exhibit a characteristic intense band at 153 cm-1. In contrast, anatase has a band of similar intensity at 144 cm-1 and rutile lacks a strong band in this region. Polarization experiments with the Brazilian crystal permit 17 out of a predicted 36 vibrational bands to be readily assigned as A1g (127, 154, 194, 247, 412, 640 cm-1), B1g (133, 159, 215, 320, 415, 502 cm-1), B2g (366, 395, 463, 584 cm-1) and B3g (452 cm-1). Eight weaker bands and component sub-bands resolved at 172, 287, 545, 618 cm-1, 254, 329, 476 cm-1 and 497 cm-1 are tentatively assigned to B3g, B2g and A1g modes respectively. Traces of Si and Fe in the Brazilian crystal and Si, Fe, Al and S in the Swiss sample are indicated by spot electron microprobe analysis. Electron spin resonance spectra suggest small amounts of Fe3+ are substituting for Ti4+ in the structure. Concomitant protonation of oxygens to maintain charge balance yields OH groups which give rise to three sharp, low-intensity absorption bands near 3360, 3380 and 3404 cm-1 in the infrared spectra. X-ray photoelectron spectroscopy shows that surface-bound OH/H2O species exist in both crystals but no detectable Ti3+.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...