ISSN:
0044-2313
Keywords:
Crystal structure
;
synthesis
;
ammine complexes
;
fluoride
;
zirconium
;
hafnium
;
Chemistry
;
Inorganic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Description / Table of Contents:
Synthesis and Crystal Structure of the Fluoride-Ammine Complexes Zr(NH3)F4 and Hf(NH3)F4Colourless, easily cleavable single crystals of Zr(NH3)F4 and Hf(NH3)F4 without special shape are obtained by oxidation of zirconium and hafnium metal powder with NH4HF2 (molar ratio 1 : 2) in sealed Monel ampoules at reaction temperatures of 380-450°C. The two fluorideammine complexes crystallize isotypically in the triclinic space group P1 (no. 2) with a = 601.4(1)/597.8(8) pm [Zr(NH3F4)/Hf(NH3)F4], b = 802.8(2)/800.6(12) pm, c = 862.3(2)/860.8(8) pm, α = 106.39(1)/106.19(10)°, β = 104.25(1)/104.51(9)°, γ = 106.83(1)/106.69(11)°, Z = 4. Bicapped trigonal prisms [M(NH3)F7] are connected via edges and corners to form corrugated layers that are held together by hydrogen bonding.
Notes:
Farblose, leicht spaltbare Einkristalle von Zr(NH3)F4 und Hf(NH3)F4 ohne ausgeprägten Habitus erhält man durch Oxidation von Zirconium- bzw. Hafnium-Metallpulver mit NH4HF2 (molares Verhältnis 1:2) in verschweißten Monelampullen bei Reaktionstemperaturen von 380-450°C. Die beiden Ammoniakate kristallisieren isotyp in der triklinen Raumgruppe P1 (Nr. 2) mit a = 601,4(1)/597,8(8) pm [Zr(NH3)F4/Hf(NH3)F4], b = 802,8(2)/800,6(I2) pm, c = 862,3(2)/860,8(8) pm, α = 106,39(1)/106,19(10)°, β = 104,25(1)/104,51(9)°, γ = 106,83(1)/106,69(11)°, Z = 4. Es liegen zweifach bekappte trigonale Prismen [M(NH3)F7] (M = Zr, Hf) vor, die über gemeinsame Kanten und Ecken zu gewellten Schichten verknüpft sind, die ihrerseits über Wasserstoffbrückenbindungen zusammengehalten werden.
Additional Material:
3 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/zaac.19976230114