Premium
Strukturelle Untersuchungen an Cs 2 [B 12 H 12 ]
Author(s) -
Tiritiris Ioannis,
Schleid Thomas,
Müller Klaus,
Preetz Wilhelm
Publication year - 2000
Publication title -
zeitschrift für anorganische und allgemeine chemie
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.354
H-Index - 66
eISSN - 1521-3749
pISSN - 0044-2313
DOI - 10.1002/(sici)1521-3749(200002)626:2<323::aid-zaac323>3.0.co;2-q
Subject(s) - chemistry , crystallography , icosahedral symmetry , crystal structure , cluster (spacecraft) , borane , aqueous solution , single crystal , catalysis , biochemistry , computer science , programming language
Structural Investigations on Cs 2 [B 12 H 12 ] The crystal structure of Cs 2 [B 12 H 12 ] has been determined from X‐ray single‐crystal data collected at room temperature. Dicesium dodecahydro‐ closo ‐dodecaborate crystallizes as colourless, face‐rich crystals (cubic, Fm 3; a = 1128.12(7) pm; Z = 4). Its synthesis is based on the reaction of Na[BH 4 ] with BF 3 (O(C 2 H 5 ) 2 ) via the decomposition of Na[B 3 H 8 ] in boiling diglyme, followed by subsequent separations, precipitations (with aqueous CsOH solution) and recrystallizations. The crystal structure is best described as anti ‐CaF 2 ‐type arrangement with the Cs + cations in all tetrahedral interstices of the cubic closest‐packed host lattice of the icosahedral [B 12 H 12 ] 2– ‐cluster dianions. The intramolecular bond lengths are in the range usually found in closo ‐hydroborates: 178 pm for the B–B and 112 pm for the B–H distance. Twelve hydrogen atoms belonging to four [B 12 H 12 ] 2– icosahedra provide an almost perfect cuboctahedral coordination sphere to the Cs + cations, and their distance of 313 pm (12 ×) attests for the salt‐like character of Cs 2 [B 12 H 12 ] according to ∞ 3 {(Cs + ) 2 ([B 12 H 12 ] 2– )}. The 11 B{ 1 H}‐NMR data in aqueous (D 2 O) solution are δ = –12,70 ppm ( 1 J B–H = 125 Hz), and δ = –15,7 ppm (linewidth: δν 1/2 = 295 Hz) for the solid state 11 B‐MAS‐NMR.