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Title: Electronic structure of Pb and non-Pb based phosphate scintillators

Abstract

The electronic structures of Pb and non-Pb containing phosphates, specifically Pb3(PO4)2, Pb2P2O7, ScPO4, YPO4 and LuPO4, are compared using a combination of density functional calculations and optical measurements. We find that the characteristic difference between these two classes are that the band gaps in the Pb containing materials are significantly lower because of the presence of Pb 6p derived bands in the gap between the valence bands and the P-O antibonding states. This may be favorable from the point of view of energy transfer in scintillator applications of Pb based phosphates. However, it also suggests that different activators than those used in other phosphate scintillators may be useful to increase the efficiency.

Authors:
 [1];  [1];  [1]
  1. ORNL
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE National Nuclear Security Administration (NNSA)
OSTI Identifier:
930758
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review B; Journal Volume: 74; Journal Issue: 15
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ELECTRONIC STRUCTURE; LEAD; LEAD PHOSPHATES; SCANDIUM PHOSPHATES; YTTRIUM PHOSPHATES; LUTETIUM PHOSPHATES; ENERGY GAP; DENSITY FUNCTIONAL METHOD; PHOSPHORS; MEASURING METHODS

Citation Formats

Singh, David J, Jellison Jr, Gerald Earle, and Boatner, Lynn A. Electronic structure of Pb and non-Pb based phosphate scintillators. United States: N. p., 2006. Web. doi:10.1103/PhysRevB.74.155126.
Singh, David J, Jellison Jr, Gerald Earle, & Boatner, Lynn A. Electronic structure of Pb and non-Pb based phosphate scintillators. United States. doi:10.1103/PhysRevB.74.155126.
Singh, David J, Jellison Jr, Gerald Earle, and Boatner, Lynn A. Sun . "Electronic structure of Pb and non-Pb based phosphate scintillators". United States. doi:10.1103/PhysRevB.74.155126.
@article{osti_930758,
title = {Electronic structure of Pb and non-Pb based phosphate scintillators},
author = {Singh, David J and Jellison Jr, Gerald Earle and Boatner, Lynn A},
abstractNote = {The electronic structures of Pb and non-Pb containing phosphates, specifically Pb3(PO4)2, Pb2P2O7, ScPO4, YPO4 and LuPO4, are compared using a combination of density functional calculations and optical measurements. We find that the characteristic difference between these two classes are that the band gaps in the Pb containing materials are significantly lower because of the presence of Pb 6p derived bands in the gap between the valence bands and the P-O antibonding states. This may be favorable from the point of view of energy transfer in scintillator applications of Pb based phosphates. However, it also suggests that different activators than those used in other phosphate scintillators may be useful to increase the efficiency.},
doi = {10.1103/PhysRevB.74.155126},
journal = {Physical Review B},
number = 15,
volume = 74,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 2006},
month = {Sun Jan 01 00:00:00 EST 2006}
}
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