A structural study of facet and off-facet parts of rare-earth garnets, Gd[sub 3]Sc[sub 2]Al[sub 3]O[sub 12], Gd[sub 3]Sc[sub 2]Ga[sub 3]O[sub 12], and La[sub 3]Lu[sub 2]Ga[sub 3]O[sub 12]

Journal Article · Sat Jan 01 00:00:00 EST 1994 · Journal of Solid State Chemistry; (United States)

DOI:https://doi.org/10.1006/jssc.1994.1014· OSTI ID:7274295

Yamazaki, Satoru; Tanaka, Kiyoaki; Morikawa, Hideki ^[1]; Marumjo, Fumiyuki ^[2]; Kodama, Nobuhiro ^[3]; Kitamjura, Kenji; Miyazawa, Yasuto ^[4]

---

1. Tokyo Institute of Technology, Yokohama (Japan)
2. Nihon Univ., Setagaya-ku, Tokyo (Japan)
3. Toyo Soda Co. Ltd., Ayase, Kanagawa (Japan)
4. National Institute for Research in Inorganic Materials, Tsukuba, Ibaraki (Japan)

The crystal structures of facet and off-facet parts of rare-earth garnets Gd[sub 3]Sc[sub 2]Al[sub 3]O[sub 12] (GSAG), Gd[sub 3]Sc[sub 2]Ga[sub 3]O[sub 12] (GSGG), and La[sub 3]Lu[sub 2]Ga[sub 3]O[sub 12] (LLGG) have been refined with the single-crystal X-ray diffraction method. The crystals are cubic with the space group Ia3d, containing eight formula units in a unit cell. The final weighted reliability factors are 0.014, 0.017, and 0.020 for 1786, 2318, and 2331 reflections of the facet parts of GSAG, GSGG, and LLGG, respectively, and 0.014, 0.017, and 0.019 for 2143, 2190, and 2420 reflections of the off-facet parts of the respective crystals. The bond lengths between the tetrahedral cations (T) and the oxygen atoms in GSAG and GSGG as well as those between the dodechedral cations (m[sup viii]) and oxygen atoms in all the examined crystals are in accordance with the sums of ionic radii both in facet and off-facet parts, whereas the octahedral cations (M[sup vi]) in all the crystals and the tetrahedral cation in LLGG have bond lengths longer than the sums of the ionic radii. A cation replacement at the T sites was not observed, whereas the M[sup vi] and M[sup viii] sites were revealed to be partly replaced by cations with smaller ionic radii.

• OSTI ID: 7274295
• Journal Information: Journal of Solid State Chemistry; (United States), Vol. 108:1; ISSN 0022-4596
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM OXIDES
CRYSTAL STRUCTURE
GADOLINIUM OXIDES
GALLIUM OXIDES
LANTHANUM OXIDES
LUTETIUM OXIDES
SCANDIUM OXIDES
ALUMINIUM COMPOUNDS
CHALCOGENIDES
GADOLINIUM COMPOUNDS
GALLIUM COMPOUNDS
LANTHANUM COMPOUNDS
LUTETIUM COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
RARE EARTH COMPOUNDS
SCANDIUM COMPOUNDS
TRANSITION ELEMENT COMPOUNDS
360202* - Ceramics
Cermets
& Refractories- Structure & Phase Studies