PRECIPITATION OF DOPANT IONS IN NACL-EU+2 CRYSTALS

Citation
T. Morawskakowal et B. Macalik, PRECIPITATION OF DOPANT IONS IN NACL-EU+2 CRYSTALS, SPECT ACT A, 54(13), 1998, pp. 2093-2097
Citations number
13
Categorie Soggetti
Spectroscopy
Journal title
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
ISSN journal
13861425 → ACNP
Volume
54
Issue
13
Year of publication
1998
Pages
2093 - 2097
Database
ISI
SICI code
1386-1425(1998)54:13<2093:PODIIN>2.0.ZU;2-B
Abstract
The aim of the work presented was to study the effect of the annealing temperature upon the formation of second phases in the NaCl matrix by using the optical absorption and ionic thermocurrent measurements. Th e 60, 125, 235 and 350 degrees C isotherms were followed mainly for cr ystals containing 120 mole ppm of divalent europium. The three lower a nnealing temperatures result in a decay of the impurity-vacancy dipole concentration up to similar to 5% of the initial value being accompan ied by the growth of metastable phases with their characteristic optic al absorption spectra previously observed for as received samples, onl y. At 350 degrees C the decay of the impurity-vacancy dipole concentra tion reaches similar to 20% of the initial value, and the newly appear ed optical absorption spectrum has been ascribed to the stable EuCl2 p recipitates with the PbCl2 type of structure. (C) 1998 Elsevier Scienc e B.V. All rights reserved.