Square planar geometry molecular

The Lewis formula predicts 6 electron groups around the central Xe atom and its electronic geometry is octahedral. The molecular geometry is square planar due to the presence of 2 lone pairs of electrons on the central Xe atom. 

The result here is quite satisfactory because XeF4 does in fact exhibit square planar geometry. It is worth noting, however, that a square planar shape for XeF4 is also predicted by VSEPR theory. Despite the fact that the molecular orbital method has made some inroads as of late, VSEPR is still the best approach available for rationalizing the molecular geometries of noble gas compounds. 

M(dmit)2 complexes (dmit = C3S52- = l,3-dithiole-2-thione-4,5-dithio-late) constitute one of the most important subclasses. The most studied metal complexes are those of group 10 (Ni, Pd, Pt), which possess a square-planar geometry see for instance the molecular structure of the monoanion [Ni(dmit)2], Figure 42.73... 

In this case, the decrease in entropy of the redox couple i.e. a decrease of the molecular disorder) is proposed to be due to the passage of the complex from the CuHIN4 square planar geometry to the usual octahedral geometry of Cu(II) complexes which requires the axial coordination of two solvent molecules (water). This reduces the disorder of the solvent molecules around the complex. 

Homoleptic phenoxido complexes of the composition [Re(L)4] where L = 2,6-diisopropylphenoxide or 2,6-dimethylphenoxide have been prepared by the reaction of [ReCl4(THF)2] with the lithium salts of the ligands. The molecular geometry is square planar and the metal center is well protected from above and below the Re04 plane by the isopropyl groups and protects the complex from reactions with alkynes, whereas such a reaction and the formation of [Re(OC6H3-2,6-Me2)4(RC=CR)] adducts (R = Me, Eth, Ph) has been observed for the dimethyl derivative of the phenoxide. ... 

Chapter 2- Transition metal dithiolenes are versatile complexes eapable of a wide range of oxidation states, coordination geometries, and magnetie moments. As a eonsequence, these complexes have been widely studied as building bloeks for erystalline molecttlar materials. Particularly successful are the square-planar metal dithiolenes (Chart 1), from which materials have been produeed that exhibit condueting, magnetic, and nonlinear optieal properties, as well as supereonduetivity in some cases. " In their application to molecular- based... 

In any molecule in which there are no nonbonding pairs around the central atom, the molecular shape is the same as the molecular geometry. Thus, to use the examples from Table 6.2, all three two-substituent molecules have both a linear geometry and a linear shape. Both BH3 and H2CO have a triangular planar shape, CH4 has a tetrahedral shape, PF5 a triangular bipyramidal shape, and SF6 a square bipyramidal shape. 

The macrocyclic phthalocyanine ligand will form a complex Pt(phthalocyanine).1106 The crystal structure shows two polymorphs present because of molecular packing.1107 The platinum is in a square planar coordination geometry with a mean Pt—N distance of 1.98 A. The complex can be partially oxidized with iodine to give conducting mixed valence solids.1108 Eighteen fundamental and overtone combination bands are observed in the resonance Raman spectrum of platinum phthalocyanine, and from this data the symmetry of the excited singlets are found to be Dy.. Qlv or D2.1109... 

The only examples of molecular geometries not explicitly covered by this model are square planar arrangements, where a central atom is surrounded by four other atoms or groups, all in a plane. Complex ions of Cu, Pd and Pt, like Cu(NH)3)J2, are examples. Here the situation is complicated by the particular arrangement of d electrons. But in Cu(NH3)J 2 in water solution there is evidence that the ion is... 

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