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Title: Optical Properties of TiO2-SiO2 Glass Over a Wide Spectral Range

Abstract

Optical properties of vitreous SiO{sub 2} with 7.4 wt.% TiO{sub 2} are found by dispersion analysis of reflectivity measured in the infrared, visible, and ultraviolet augmented with literature values of vacuum-ultraviolet reflectivity and absorption. The principal infrared absorption associated with the titanium dopant occurs at 950 cm{sup -1} in a deep minimum of the host silica absorption. We attribute this to a perturbation of the silica's absorption at 1076 cm{sup -1} involving oxygen atoms bridging SiO{sub 4} and TiO{sub 4} tetrahedra. Strong ultraviolet absorptions of Ti{sup 4+} occur just below the silica exciton peak between 5.5 and 7.8 eV. We attribute these to charge-transfer transitions at TiO{sub 4} tetrahedra; i.e., bound excitons consisting of a Ti{sup 3+} ion and a hole shared by four oxygen neighbours.

Authors:
; ; ;
Publication Date:
Research Org.:
Brookhaven National Laboratory (BNL) National Synchrotron Light Source
Sponsoring Org.:
Doe - Office Of Science
OSTI Identifier:
930409
Report Number(s):
BNL-81139-2008-JA
Journal ID: ISSN 1610-1634; TRN: US0901382
DOE Contract Number:
DE-AC02-98CH10886
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physica Status Solidi C; Journal Volume: 4; Journal Issue: 3
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ABSORPTION; ATOMS; EXCITONS; GLASS; OPTICAL PROPERTIES; OXYGEN; REFLECTIVITY; SILICA; TITANIUM; national synchrotron light source

Citation Formats

Smith,D., Black, C., Homes, C., and Shiles, E. Optical Properties of TiO2-SiO2 Glass Over a Wide Spectral Range. United States: N. p., 2007. Web. doi:10.1002/pssc.200673847.
Smith,D., Black, C., Homes, C., & Shiles, E. Optical Properties of TiO2-SiO2 Glass Over a Wide Spectral Range. United States. doi:10.1002/pssc.200673847.
Smith,D., Black, C., Homes, C., and Shiles, E. Mon . "Optical Properties of TiO2-SiO2 Glass Over a Wide Spectral Range". United States. doi:10.1002/pssc.200673847.
@article{osti_930409,
title = {Optical Properties of TiO2-SiO2 Glass Over a Wide Spectral Range},
author = {Smith,D. and Black, C. and Homes, C. and Shiles, E.},
abstractNote = {Optical properties of vitreous SiO{sub 2} with 7.4 wt.% TiO{sub 2} are found by dispersion analysis of reflectivity measured in the infrared, visible, and ultraviolet augmented with literature values of vacuum-ultraviolet reflectivity and absorption. The principal infrared absorption associated with the titanium dopant occurs at 950 cm{sup -1} in a deep minimum of the host silica absorption. We attribute this to a perturbation of the silica's absorption at 1076 cm{sup -1} involving oxygen atoms bridging SiO{sub 4} and TiO{sub 4} tetrahedra. Strong ultraviolet absorptions of Ti{sup 4+} occur just below the silica exciton peak between 5.5 and 7.8 eV. We attribute these to charge-transfer transitions at TiO{sub 4} tetrahedra; i.e., bound excitons consisting of a Ti{sup 3+} ion and a hole shared by four oxygen neighbours.},
doi = {10.1002/pssc.200673847},
journal = {Physica Status Solidi C},
number = 3,
volume = 4,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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