Trigonal bipyramidal molecular

Especially notable is also the synthesis and structural characterization of an unusual antimony(III) guanidinate. 1,2,3-Tiiisopropylguanidine, Pr N = C(NHPr )2,was found to react with 1 molar equivalent of Sb(NMe2)3 in toluene under formation of a yellow solution, from which the novel compound Sb[Pr NC(NPr )2][Pr NHC(NPr )2] could be isolated in 10% yield as highly air-sensitive crystals. In the solid state, the complex adopts a heavily distorted trigonal-bipyramidal molecular structure in which the Sb is chelated by a [CfNPr ls] dianion and a [Pr NHC(NPr )2] monoanion (Figure 16). Supramolecular... 

Just zinc complexes bearing redox-active ligands sometimes display apparently reversible redox processes. Really, in these cases the electron transfer processes are centred on the ligand. This is, for example, the case of [Zn(papm)Cl2] (papm = 2-(phenylazo)pyrimidine), the (distorted) trigonal bipyramidal molecular structure of which is illustrated in Figure 134.194... 

Binary Systems and Related Compounds.—Halides. The thermodynamics of gas-phase equilibria in the W-F2 and W-F2-H2 systems at high temperatures have been described.The Raman spectrum of solid MoF exhibits Mo—F stretching bands at 746, 722, and 690 cm These results suggest that the compound has a similar structure to NbF4, with each molybdenum co-ordinated to six fluorine atoms.The Raman spectrum of crystalline M0F5 has also been reported and interpreted in terms of the crystal structure.The electronic spectrum of liquid M0F5 has been determined and shown to be consistent with a trigonal-bipyramidal molecular unit. ... 

Five-coordinate intermediates having trigonal bipyramidal molecular geometries have been isolated in several cases, including, for example, [Ni(CN)5] and [Pt(SnCl3)s]3-. 

When there are five electron groups around the central atom, it is sp d hybridized. AB5 molecules and ions with no lone pairs on the central atom have trigonal bipyramidal electronic geometry, trigonal bipyramidal molecular geometry, and sp d hybridization on the central atom. 

To describe hybridization schemes that correspond to the 5- and 6-electron-group geometries of VSEPR theory, we need to go beyond the s and p subshells of the valence shell, and traditionally this has meant including d-orbital contributions. We can achieve the five half-filled orbitals of phosphorus to account for the five P—Cl bonds in PCI5 and its trigonal-bipyramidal molecular geometry through the hybridization of the s, three p, and one d orbital of the valence shell into five sp d hybrid orbitals. 

Mixed pentahalides are more readily isolated and are of at least three types ionic, tetrameric, and less stable molecular trigonal-bipyramidal monomers. Thus, chlorination of a mixture of ASF3/ASCI3 with CI2, or fluor-ination of AsCU with CIF3 (p. 828) gives [AsCl4]" [AsF6] [mp 130°(d)] whose X-ray... 

An interesting feature of phosphorus pentachloride is that it is an ionic solid of tetrahedral PC14+ cations and octahedral PC16 anions, but it vaporizes to a gas of trigonal bipyramidal PC15 molecules (see Section 2.10). Phosphorus pentabromide is also molecular in the vapor and ionic as the solid but, in the solid, the anions are simply Br ions, presumably because six bulky Br atoms simply do not fit around a central P atom. 

C09-0129. Tellurium compounds, which are toxic and have a hideous stench, must be handled with extreme care. Predict the formula of the tellurium-fluorine molecule or ion that has the following molecular geometry (a) bent (b) T-shaped (c) square pyramid (d) trigonal bipyramid (e) octahedron and (Q seesaw. 

These compounds are often referred to as hypervalent. The apical bonds in a trigonal bipyramid are described by molecular orbitals constructed from a p-orbital on the central atom and o-bonding orbitals (p- or sp hybrid) on the apical ligands. The molecular orbitals can be drawn as ... 

The resemblance of the coordination polyhedra in 9 and 10 is really amazing. The same is true for two F-trigonal bipyramidal arrangements as a comparison of the ionic compound molecular complex Sn( OC(Ph)CHC(Me)=0)2 (12) 37), which contains two chelating acetylacetonato ligands, reveals. 

Figure 80 Trigonal bipyramidal coordination capsule with a chemical formula of C H igNdosPdig, a molecular mass of 7,103 Da, and a dimension of 3 x 2.5 x 2.5 nm.

A series of copper(II) complexes with ring-substituted phen-ligands have been synthesized and their molecular structural and electronic structural properties have been investigated.246 Each structure ((280) r = 0.72, (281) r = 0.81, (282) r = 0.88, (283) r = 0.83, and (284) r = 0.68) is characterized by a distorted trigonal-bipyramidal arrangement of ligands around copper. 

These conclusions can be drawn by simple inspection of the molecular orbitals of PHS. The next question is the energetics of the interconversions of the various conformations. The result sketched in Fig. 27 refers to the Berry pseudorotation (J5) process of PHS. The square pyramid is a transition state for isomerization of the trigonal bipyramid, but the barrier is extremely small, in agreement with available experimental evidence. The more complex process ... 

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