Tricapped trigonal prismatic

Chlorides. The oHve-green trichloride [10025-93-1], UCl, has been synthesized by chlorination of UH [13598-56-6] with HCl. This reaction is driven by the formation of gaseous H2 as a reaction by-product. The stmcture of the trichloride has been deterrnined and the central uranium atom possesses a riine-coordinate tricapped trigonal prismatic coordination geometry. The solubiUty properties of UCl are as follows soluble in H2O, methanol, glacial acetic acid insoluble in ethers. 

Key Colour % indicates preparation but no report of colour) mp/°C (na indicates value not reported) coordination 9 ttp = tricapped trigonal prismatic 8 d = dodecahedral 8 sa = square antiprismatic 8 btp = bicapped trigonal prismatic 8,7 = mixed 8- and 7-coordination (SrBr2 structure) 7 cc = capped octahedral 7 pbp = pentagonal bipyramidal 6 o = octahedral 6 och = octahedral chain, 6 ol = octahedral layered. 

U pm) as would be required for tricapped trigonal prismatic geometry the bonding B-B contacts are all within the normal range. 

Nine-coordinate (each NOj group is bidentate) tricapped trigonal prismatic structure... 

Fig. 1-14. Comparison of NICS for boron clusters top row, nine-vertex D tricapped trigonal prismatic clusters bottom row, four-vertex 7]j tetrahedral clusters.

Na3[Ln(C7H3N04)3],nH20 (Ln = Yb, n = 13, Ln = Nd, n = 15) are nine-co-ordinate having a distorted tricapped trigonal prismatic arrangement of six carboxylate O atoms and three N atoms. 

In contrast to the monoclinic tris-malonato complexes, M2(OOCCH2COO)s 8 H2O (M=Nd) which contain nonacoordinated lanthanide ions in a monocapped square antiprismatic polyhedron, the orthorhombic tris-malonates Pnma) have a tricapped trigonal prismatic geometry for the coordination polyhedron. A rep-... 

Fig. 33. The tricapped trigonal prismatic coordination polyhedron around Eu(III) in Eu(OHCH2COO)s complex...

Cationic deltahedral Pn clusters are known for Pn=Bi. [Bis], [Big], and [Bi9], which have been structurally characterized with complex counterions such as AlCLt, AsFg, and HfCle , can be obtained either by molten salt routes or by using so-called super acidic systems [205-209]. According to Wade s formalism, [Bis] " " and [Big] correspond to 12 ske closo and 22 ske arachno structures, respectively, and the latter adopts the shape of a square antiprism. [Bi9] " which is expected to form a 22 ske nido-cluster in analogy to Fig. 2d, rather adopts a distorted tricapped trigonal prismatic topology (Fig. 2c). 

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