High-pressure synthesis and single-crystal structure refinement of gadolinium holmium silicate hydroxyapatite Gd{sub 4.33}Ho{sub 4.33}(SiO{sub 4}){sub 6}(OH){sub 2}

Journal Article · Sat Jul 15 04:00:00 EDT 2006 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/j.jssc.2006.03.047· OSTI ID:20905372

Chao, Wang ^[1]; Xiaoyang, Liu ^[1]; Fleet, M E ^[2]; Feng, Shouhua ^[1]; Ruren, Xu ^[1]

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1. State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012 (China)
2. Department of Earth Sciences, University of Western Ontario, London, Ont., N6A 5B7 (Canada)

Single crystals of gadolinium holmium silicate hydroxyapatite Gd{sub 4.33}Ho{sub 4.33}(SiO{sub 4}){sub 6}(OH){sub 2} have been synthesized at 2.0GPa and 1450 deg. C using a piston-cylinder-type high-pressure apparatus. The crystal symmetry by single-crystal X-ray diffraction analysis is hexagonal, space group P6{sub 3}/m (No. 176), with a=9.3142(5)A, c=6.7010(4)A, Z=1. Gadolinium and Ho are disordered over the two large cation positions, A(1) and A(2), and charge balance in this silicate apatite is maintained by cation vacancies in A(1). Two other apatite-structure crystals investigated have P3-bar and Imma symmetry, and represent either partially ordered Gd-Ho distributions or crystal strain induced during quenching.

• OSTI ID: 20905372
• Journal Information: Journal of Solid State Chemistry, Journal Name: Journal of Solid State Chemistry Journal Issue: 7 Vol. 179; ISSN 0022-4596; ISSN JSSCBI
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
APATITES
GADOLINIUM COMPOUNDS
HEXAGONAL LATTICES
HOLMIUM SILICATES
MONOCRYSTALS
QUENCHING
SPACE GROUPS
STRAINS
SYNTHESIS
TEMPERATURE RANGE 1000-4000 K
TETRAGONAL LATTICES
TRIGONAL LATTICES
VACANCIES
X-RAY DIFFRACTION