Octahedral structure

Fluoride complexes of silver(III) are exemplified by the purple-red Cs2KAgF6 (elpasolite structure, octahedral Ag3+ paramagnetic with /x = 2.6/ub). Yellow MAgF4 (M = Na, Rb, K) and XeF AgF4 are diamagnetic and probably square planar [65],... 

The structure of [Mo3S4(dmit)3] (dmit=l,3-dithiole-2-thione-4,5-dithiolate) represents one of the rare examples of M3S4 clusters where each metal atom appears as pentacoordinate instead of its more common type-I structure octahedral environment [39]. Complexes [M3Q4(dmit)3] (M = Mo, W Q = S, Se) degrade in air with an almost quantitative yield and afford a series of M(V) dimers of formula [M202(//-Q)2(dmit)2] where the oxygen atoms are in a syn configuration. 

Clay Minerals as Lewis Acids. Lewis acid sites in a clay mineral are exchangeable (2) or structural ( 0) transition metal cations in the higher valence state, such as Fe + and Cu +, and octahedrally coordinated aluminum exposed at the crystal edges (38). Reduction of both exchanged and structural (octahedral) transition metal cations in the upper oxidation state is a reversible process (12,... 

There are two types of interstices in the hep structure octahedral and tetrahedral holes, as in the ccp structure. However, the hep and ccp structures differ in the linkage of interstices. In ccp, neighboring octahedral interstices share edges, and the tetrahedral interstices behave likewise. In hep, neighboring octahedral interstices share faces, and a pair of tetrahedral interstices share a common face to form a trigonal bipyramid, so these two tetrahedral interstices cannot be filled by small atoms simultaneously. Figure 10.2.1 shows the positions of the octahedral interstices (a) and tetrahedral interstices (b). Table 10.2.1 lists the pure metals with hep structure and the parameters of the unit cell. 

Review of Reported Structures. A theoretical analysis of XANES profiles at the Ljjj edge of platinum in PtCl/ and PtCltf 2 was presented by Nemarova, et al. (24). However, in assigning transitions from the 2p states to vacant bound orbitals, these authors postulated highly symmetric structures [octahedral and square configurations]. It is doubtful that the corresponding orbital designations correctly apply to the distorted fields that exist on the surfaces of these supported catalysts. 

The pyrophosphate of uranium(IV) has been obtained and the structure determined to belong to the ZrP207-type structure. " Octahedral sites in the zirconium phosphates can accommodate U, as exemplified by the Na dizirconium tris(phosphate) structural family ([NZP]). An end member in this study was monoclinic KU2Zr(P04)3, which contains nine-coordinate Compounds of the general formula MU2(P04)3 have been reported for... 

In the Cdlj structure, octahedral sites between every other pair oi hep layers of iodine atoms are occupied by cadmium atoms CdCU has cadmium in octahedral sites between cep layers. Actually, matters can get much more complicated than that There are three different Cdlj slmclures with varied layers. To indicate the potential complexity without going into the details of the several po.ssibilities, the structure of one form of CdBrl will be mentioned It has a twelve-layer repeating unit of halide ions, ABCBCABABCAC, surely long-range order of a fairly high degree. 

KSb03 is prepared by heating KSb(OH)6 and is trimorphic. One form has the ilmenite structure, and the other a cubic structure illustrated in Fig. 5.33 (p. 183). In the latter structure octahedral SbOg groups share edges and vertices, and this is also true of K3SbsOi4. There Is apparently no compound K2Sb20j. 

C2B4H6 has (6 X 2) + 2 = 14 skeletal electrons or seven skeletal electron pairs. This corresponds to + 1, or a closo structure (octahedral). 

Na, metal Cdl2, layered structure octahedral site, 6-... 

From reactions of binary hydrides MH with T at 753 K and 10 bar hydrogen pressure no compound formation with KH and Fe up to 1073 K and 100 bar Ru does not react with KH, and Os not with NaH and KH under experimental conditions powders either white (Li) or green (Na) all air sensitive ordered structures (Figure 11) from npd at room temperature on deuterides R3c, Z = 6 (hexsetting), K4CdCl6 type structure octahedral [THe] 18-electron complex with T site symmetry 3 surrounded by two M sites in nearly cubic configuration one D site lif 4M+-[TH6] T = Ru, Os , d . Interatomic distances are given in Table 8. 

Data are presented in five tables. Table 1 lists the main crystallographic and semiconducting properties of a large number of semiconducting materials in three main categories Tetrahedral Semiconductors in which every atom is tetrahedraUy coordinated to four nearest neighbor atoms (or atomic sites) as for example in the diamond structure Octahedral Semiconductors in which every atom is octahedrally coordinated to six nearest neighbor atoms—as for example the halite structure and Other Semiconductors. ... 

The M"MF6-6H20 compounds are isostructural with FeSiF6-6H20 (space group R3m), which is known to contain octahedral [Fe(H20)6] and [SiFe] ions in a slightly distorted CsQ structure" octahedral... 

Brown and co-workers reported the formation of completely condensed cubic cage-structured octahedral octaphenylsilsesquioxane (Ph-Tg). The other typical cage is decahedral decasilsesquioxane, Tm-... 

Na, metal Cdl2, layered structure octahedral site, 6-coordinate Ga-doped Si, extrinsic semiconductor Na2S, antifluorite structure perovskite, double oxide CaF2, fluorite structure GaAs, intrinsic semiconductor wurtzite and zinc blende, polymorphs Sn02, cassiterite. 

SiF4, gas, tetrahedral molecules Si, semiconductor CS3C50, superconducting at 40 K SnO, amphoteric [Gej]", Zintl ion GeFz, carbene analogue [Si04]" , salt is component of cement PbOz, acidic oxide Pb(N03)z, water-soluble salt not decomposed SnF4, sheet structure, octahedral Sn. 

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