What is the molecular geometry of XeF4?

The molecular geometry of xenon tetrafluoride (XeF4) is square planar. This geometry arises because XeF4 has a central xenon atom bonded to four fluorine atoms, with two lone pairs of electrons also present on the xenon.

To determine the molecular geometry, we look at the steric number, which is the sum of the number of bonded atoms and lone pairs around the central atom. In this case, xenon is bonded to four fluorine atoms, contributing four to the steric number, and the two lone pairs contribute an additional two. This results in a steric number of six.

In a molecule with a steric number of six, the ideal arrangement of electron pairs is octahedral. However, the presence of the two lone pairs alters the arrangement; these pairs occupy positions opposite to each other in order to minimize repulsion. The four fluorine atoms then occupy the equatorial plane of the octahedral arrangement, leading to a square planar geometry for the molecule.

This geometry leads to the characteristic angles and arrangement observed in XeF4, making it a typical example of how lone pairs affect molecular shape.