Trigonal bipyramidal arrangement

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. 

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. 

The crystal structure of the C-functionalized imidazole derivative of 1,5,9-triazcyclododecane (75) shows a five-coordinate zinc with four /V-donors from ligand and chloride in a distorted trigonal bipyramidal arrangement. The Zn—N imidazole bonds are the shortest at 2.025(3) A.678 Deprotonation of the imidazole group resulted in a bridging imidazolate to form dinuclear zinc complexes. The pATa of 10.3 varies from the pATa of bound water with similar ligands (as low as 7.3) and the complex is not catalytic for the hydrolysis of esters. 

According to the VSEPR model the T-shaped CIF3 molecule has a trigonal bipyramidal arrangement of three bonding electron pairs and two nonbonding electron pairs in the valence shell of the central Cl atom. 

Manganese can also be a catalyst. Manganese [as Mn(III)] in superoxide dismutase from Thermus thermophilus (Stallings et al., 1984, 1985) is surrounded by three histidines, one aspartate oxygen, and water in a trigonal bipyramidal arrangement. The fifth coordination site is occupied by a water molecule. In copper, zinc-superoxide dismutase (Cu,Zn = SOD), as described later, there are two metals (copper and zinc). Each bonds to and are separated by this same histidine group. 

The structure of the cationic part of 7 consists of a [Mg3C2] trigonal bipyramidal arrangement (Figure 8) with the magnesium atoms in the equatorial plane and the carbon atoms at the apical positions. The two allyl groups are /r3-bonded (one above and one... 

CH2NMe2)2], initially produces the tricyclic compound Ar3Sb5 with a trigonal bipyramidal arrangement of five Sb atoms. ... 

These lowest oxidation states can be associated with a coordination number of two and a linear arrangement of the ligands about the central atom. On VSEPR theory these are 10-electron species, with a trigonal bipyramidal arrangement of three lone pairs of electrons in equatorial positions and two halogen ligands in axial positions. 

Another useful member of the vanadium oxide group is the LiVsOg vanadium bronze. Its basic structure is formed by octahedral and trigonal bipyramids arranged to form puckered layers between which the Li+ ions... 

More recently, the crystal structures of several silver sulfonates have been determined those containing methanesulfonate,332 bromomethanesulfonate333 and pyridinesulfonate.334 In the first of these, no distinct molecule of the silver salt was found in the unit cell. The silver atom was five-coordinate with a very distorted trigonal bipyramidal arrangement. Ag—O bond distances were in the range 234-263 pm. Each silver was bound to five different methanesulfonates.332... 

The structure of the [Fe(Et2Dtc)2] 2 complex that was synthesized previously (236, 512) has been determined (354). The iron atoms in the dimer are surrounded by a distorted trigonal bipyramid arrangement of the sulfur donors (Fig. 31). 

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