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Title: Optical absorption edge in rare earth sesquisulfides

Abstract

Optical absorption edge spectra have been measured by diffuse reflectance spectroscopy on a complete suite of rare earth sesquisulfide compounds of varying structure type. Optical band gaps were extracted from these data. The observed band gaps tend to vary with crystal structure type but many compounds with the same structure have similar band gaps independently of the particular rare earth ion. The ordered {alpha}-structure has a substantially lower band gap than the defect {gamma}-structure for all compounds examined except for La{sub 2}S{sub 3}.

Authors:
 [1];  [2]
  1. Materials Research Institute, Pennsylvania State University, University Park, PA 16802 (United States)
  2. Materials Research Institute, Pennsylvania State University, University Park, PA 16802 (United States). E-mail: wbw2@psu.edu
Publication Date:
OSTI Identifier:
20891634
Resource Type:
Journal Article
Resource Relation:
Journal Name: Materials Research Bulletin; Journal Volume: 41; Journal Issue: 2; Other Information: DOI: 10.1016/j.materresbull.2005.07.035; PII: S0025-5408(05)00297-7; Copyright (c) 2005 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ABSORPTION; CRYSTAL DEFECTS; CRYSTAL STRUCTURE; LANTHANUM SULFIDES; OPTICAL PROPERTIES; RARE EARTHS; SPECTROSCOPY

Citation Formats

Forster, Cheryl M., and White, William B.. Optical absorption edge in rare earth sesquisulfides. United States: N. p., 2006. Web. doi:10.1016/j.materresbull.2005.07.035.
Forster, Cheryl M., & White, William B.. Optical absorption edge in rare earth sesquisulfides. United States. doi:10.1016/j.materresbull.2005.07.035.
Forster, Cheryl M., and White, William B.. Thu . "Optical absorption edge in rare earth sesquisulfides". United States. doi:10.1016/j.materresbull.2005.07.035.
@article{osti_20891634,
title = {Optical absorption edge in rare earth sesquisulfides},
author = {Forster, Cheryl M. and White, William B.},
abstractNote = {Optical absorption edge spectra have been measured by diffuse reflectance spectroscopy on a complete suite of rare earth sesquisulfide compounds of varying structure type. Optical band gaps were extracted from these data. The observed band gaps tend to vary with crystal structure type but many compounds with the same structure have similar band gaps independently of the particular rare earth ion. The ordered {alpha}-structure has a substantially lower band gap than the defect {gamma}-structure for all compounds examined except for La{sub 2}S{sub 3}.},
doi = {10.1016/j.materresbull.2005.07.035},
journal = {Materials Research Bulletin},
number = 2,
volume = 41,
place = {United States},
year = {Thu Feb 02 00:00:00 EST 2006},
month = {Thu Feb 02 00:00:00 EST 2006}
}
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