Synthesis by hydrogen-driven disproportionation reactions. Synthesis and structure of the hexazirconium dodecahalide clusters Zr/sub 6/Cl/sub 12/ and Zr/sub 6/Br/sub 12/ and the double salt Zr/sub 6/Cl/sub 12/. M/sub 2/ZrCl/sub 6/(M = Na, K, Cs)

Journal Article · Thu Jan 01 04:00:00 EST 1981 · Inorg. Chem.; (United States)

DOI:https://doi.org/10.1021/ic50215a031· OSTI ID:6607460

Imoto, H; Corbett, J D; Cisar, A

The ZrXH phases, X = Cr, Br, formed by reaction of H/sub 2/ with double-metal-layered ZrX at 150 to 450/sup 0/ are metastable and decompose at 630 to 780/sup 0/C to ZrH/sub 2/ plus the cluster compound Zr/sub 6/H/sub 12/, the latter being isostructural with Zr/sub 6/I/sub 12/. Transport of Zr/sub 6/Cl/sub 12/ occurs in the sealed Ta container at about 800/sup 0/C. The two cluster phases are also formed as powders from incomplete reactions of ZrX and ZrX/sub 4/ at 650 to 700/sup 0/C, while the layered 3R-ZrCl/sub 2/ is more stable at lower temperatures. Decomposition of ZrClH in the presence of NaCl, or CsCl at 750/sup 0/C yields the isostructural M/sub 2/Zr/sub 7/Cl/sub 18/ (M = Na, K, Cs) while ZrCl does not react with NaCl or KCl alone under the same conditions. The crystal structure of the double salt K/sub 2/Zr/sub 7/Cl/sub 18/ was solved by single-crystal diffractometer methods (R anti 3, a = 9.499 (2) A, c = 25.880 (6) A, R = 0.037, R/sub w/ = 0.049, 736 Mo K..cap alpha.. diffractions corrected for absorption). The structure contains the octahedral metal cluster Zr/sub 6/Cl/sub 12/ slightly compressed along the anti 3 axis (d(Zr-Zr) = 3.224 (1), 3.178 (1) A) and edge bridged by chlorine. Halides in octahedral ZrCl/sub 6//sup 2 -/ groups occupy all exo positions of the clusters. The structure can also be described in terms of nine chlorine layers per cell containing regular potassium and vacancy substitutions together with zirconium (II) and zirconium (IV) in octahedral interstices. The Zr/sub 6/Cl/sub 12/ and Na/sub 2/Zr/sub 7/Cl/sub 18/ phases quenched in the presence of hydrogen at approx. 1 atm do not contain hydrogen in the clusters.

• Research Organization: Iowa State Univ., Ames
• DOE Contract Number: W-7405-ENG-82
• OSTI ID: 6607460
• Journal Information: Inorg. Chem.; (United States), Journal Name: Inorg. Chem.; (United States) Vol. 20:1; ISSN INOCA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
ALKALI METAL COMPOUNDS
BROMIDES
BROMINE COMPOUNDS
CESIUM CHLORIDES
CESIUM COMPOUNDS
CHEMICAL REACTIONS
CHLORIDES
CHLORINE COMPOUNDS
CRYSTAL STRUCTURE
DECOMPOSITION
HALIDES
HALOGEN COMPOUNDS
HYDRIDES
HYDROGEN COMPOUNDS
POTASSIUM CHLORIDES
POTASSIUM COMPOUNDS
SODIUM CHLORIDES
SODIUM COMPOUNDS
TRANSITION ELEMENT COMPOUNDS
ZIRCONIUM BROMIDES
ZIRCONIUM CHLORIDES
ZIRCONIUM COMPOUNDS
ZIRCONIUM HYDRIDES