Cation geometry square pyramidal

X = F, Cl, and Br, contains the oxochromium(V) cation [23411-25-8], CrO ", exhibits a square pyramidal geometry. Compounds containing this cation are among the most stable Cr(V) compounds. 

With P-donors a variety of different structures are formed. Two complexes (359a,b) with a five-coordinate square pyramidal geometry and one S-donor in the apical position are reported.934,933 In a related complex (360) the nickel center reveals a distorted square planar geometry, because one xanthate ligand switched to a monodentate coordination mode. 6 By reaction of [NiL2] complexes with Ph2P(CH2)2P(Ph)(CH2)2PPh2, compound (362) is formed, which consists of a five-coordinate cation and a hexacoordinate anion. 7... 

The analogous cationic pyridylbis(oxazoline)-copper complexes exhibit square pyramidal geometries in the solid state. As in the bis(oxazoline) series, the triflate is closer to the metal than the SbF6 counterion (2.36 and 2.49 A vs 2.90 A). A single molecule of water is bound to the copper center in the triflate complex 267b, whereas the SbF6 complex 268b accommodates two water molecules in the coordination sphere, Fig. 24 (197). 

The reaction of [TcOCU] with various monodentate aromatic thiols in methanol produces complexes of the general formula [TcO(SAr)4] (89), which can be precipitated with bulky cations. The X-ray crystal structure of the complex with Ar = mesityl has been elucidated and has square-pyramidal geometry, with the Tc atom displaced from the basal plane by about 0.846 Direct... 

The tetranuclear sulfur and selenium derivatives [E(AuPPh3)4]2+ show a square pyramidal geometry with the chalcogen atom in the apical position [241]. These cations dimerize in the solid state through Au-E interactions (Figure 1.40). Further auration of sulfur and selenium to give the penta- and hexa-nudear species has been achieved and trigonal bipyramidal and octahedral structures have been proposed [242]. 

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