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Ζ. Kristallogr. N C S 2 1 6 ( 2 0 0 1 )© by Oldenbourg Wissenschaftsverlag, München
Refinement of the crystal structure of gallium trifluoride, GaF3
M . R o o s a n d G . M e y e r *
Universität zu Köln. Institut für Anorganische Chemie, Greinstraße 6. D-50939 Köln, Germany
Received July 14. 2000. CSD-No. 409507
[GaF
6]
c
A
Discussion
G a F j c r y s t a l l i z e s in the VF3 t y p e o f structure w i t h the h e x a g o n a l s p a c e g r o u p R3c [ 1 ]. A p r e v i o u s d e s c r i p t i o n o f the crystal struc- ture [ 2 ] u s e s the r h o m b o h e d r a l s e t t i n g o f the s p a c e group. T h e c e l l p a r a m e t e r s o b t a i n e d b y p o w d e r d i f f r a c t i o n r e f i n e m e n t are a = 4 . 9 9 5 ( 1 ) Ä a n d c = 1 3 . 0 6 3 ( 4 ) Ä . G a F3 is b u i l t o f a t h r e e - d i m e n s i o n a l n e t w o r k o f [ G a F ö ] o c t a h e d r a sharing c o m m o n corners w i t h a G a - F - G a a n g l e o f 1 4 7 . 7 9 ( 8 ) ° .
Table 1. Data collection and handling.
Crystal: colourless, square-formed, nearly cubic.
size 0.16 x 0.20 x 0.20 mm Wavelength: Mo Ka radiation (0.71073 A)
μ: 143.37 cm"1
Diffractometer, scan mode: STOE 1PDS, φ
26max: 55.7°
WlW)measured, N(hkl)umqm: 726, 77
Criterion for lob·,. N(hkl)sc /obs > 2 af/obsi. 74 N(param)Kfi ncd'· 8
Programs: SHELXS-97 [3], SHELXL-97 [4),
DIAMOND [5]
>a
Acknowledgment. We are grateful to the Deutsche Forschungsgemeinschaft, Bonn, for financial support.Abstract
F3G a , trigonal, R3c ( N o . 167), a = 5 . 0 1 2 ( 4 ) A , c = 1 2 . 9 9 ( 1 ) Ä , V= 2 8 2 . 6 Ä3, Z = 6 , R&(F) = 0 . 0 2 2 , w R n f i F2) = 0 . 0 5 3 , T = 2 9 3 K.
Source of material
G a F3 m a y b e o b t a i n e d through the reaction o f g a l l i u m metal ( V e n t r o n 4 N ) w i t h NH4F ( M e r c k , 9 9 , 8 %, r e c r y s t a l l i z e d f r o m C H 3 O H t o r e m o v e traces o f w a t e r ) in the m o l a r ratio o f 1:3 in a s e a l e d M o n e l container. T h e reaction temperature i s 7 4 8 Κ w i t h a c r y s t a l l i z a t i o n t i m e o f s i x w e e k s . C o l o u r l e s s square s h a p e d nearly c u b i c c r y s t a l s are o b t a i n e d [1].
Table 2. Atomic coordinates and displacement parameters (in Ä2).
References
1. Roos, M.: Aufbau und Abbau komplexer Ammoniumfluorometallate der Elemente Aluminium, Gallium und Indium unter Ammoniakatmosphäre.
Dissertation, Universität zu Köln, Germany 1999.
2. Brewer, F. Μ.; Garton, G.; Goodgame, D. M. L.: The preparation and crys- tal structure of gallium trifluoride. J. Inorg. Nucl. Chem. 9 (1959) 56.
3. Sheldrick, G. M.: SHELXS-97-2, Program for the Solution of Crystal Structures. University of Göttingen, Germany 1997.
4. Sheldrick, G. M.: SHELXL-97-2, Program for Crystal Structure Refine- ment. University of Göttingen, Germany 1997.
5. Brandenburg, K.: Diamond (Version 2.1 a). Crystal Impact GbR, Germany 1996-1999.
Atom Site X ί- Ζ U n U22 t/33 U η t / n Uli
Ga 6b 0 ο 0 0.0033(4) U η 0.0030(5) 0.0016(2) 0 0
F 18e 0.0591(3) jc-1/3 1/12 0.0090(7) U ι. 0.0083(7) 0.0057(7) -0.0020(3) -Uli
* Correspondence author (e-mail: gerd.meyer@uni-koeln.de)
