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Crystal structure of new phosphates Ca9–xPbxEu(PO4)7 from Rietveld refinement

Published online by Cambridge University Press:  23 April 2015

Dina Deyneko*
Affiliation:
Department of Chemistry, Lomonosov Moscow State University, Leninskie gory, d. 1, Moscow, Russia
Sergey Stefanovich
Affiliation:
Department of Chemistry, Lomonosov Moscow State University, Leninskie gory, d. 1, Moscow, Russia
Bogdan Lazoryak
Affiliation:
Department of Chemistry, Lomonosov Moscow State University, Leninskie gory, d. 1, Moscow, Russia
*
a)Author to whom correspondence should be addressed. Electronic mail: [email protected]

Abstract

New phosphates Ca9–xPbxEu(PO4)7 were obtained by solid state reaction techniques at 1213–1253 K in air atmosphere and were found to be isotypic with whitlockite-type β-Ca3(PO4)2. The unit cell parameters were determinate using Le Bail decomposition. Rietveld method structural refining showed that Eu3+ ions are located statistically with calcium in M1, M2, and M3 sites, whereas Pb2+-ions are preferentially located in the M3. Examination of optical second harmonic generation evidences nonlinear optical activity and confirms polar space group R3c.

Type
Technical Articles
Copyright
Copyright © International Centre for Diffraction Data 2015 

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