Five Electron Groups Trigonal Bipyramidal Geometry

Five Electron Groups Trigonal BIpyramidal Geometry 

The three equatorial chlorine atoms are separated by 120° bond angles and the two axial chlorine atoms are separated from the equatorial atoms by 90° bond angles. 

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Five Electron Groups Trigonal BIpyramidal Geometry... 

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. 

The central atom, S, is bonded to four atoms and has one lone pair. This is an example of the general formula AB4U. Sulfur has five electron groups, so we know that the electronic geometry is trigonal bipyramidal and the bonding orbitals are sp d hybrids. But now a new question arises Is the arrangement more stable with the lone pair in an axial (a) or in an equatorial (e) position If it were in an axial position, it would be 90° from the three closest... 

Trigonal bipytamidal A term used to describe the electronic geometry around a central atom that has five electron groups. Also used to describe the molecular geometry of a molecule or polyatomic ion that has one atom in the center bonded to five atoms at the corners of a trigonal bipyramid (AB5). 

For More Practice There are five electron groups about the central atom (1) therefore, the electron geometry is trigonal bipyramidal and the corresponding hybridization of I is sp d (refer to Table 10.3). 

The krypton atom in krypton difluoride does not obey the octet rule. The presence of five pair around the krypton leads to a trigonal bipyramidal electron-group geometry. The presence of three lone pairs and two bonding pairs around the krypton makes the molecule linear. The two krypton-fluorine bonds are polar covalent. However, in a linear molecule, the bond polarities pull directly against each other and cancel. Cancelled bond polarities make the molecule nonpolar. The strongest intermolecular force in the nonpolar krypton difluoride is London force. 

Since arsenic and phosphorus are both in the same group of die periodic table, this problem is exactly like Problem 10.40. AsFs is an AB5 type molecule, so the geometry is trigonal bipyramidal. We conclude that As is sp d hybtidized because it has the electron arrangement of five sp d hybrid orbitals. 

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. 

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