XeF4 Lewis Structure
Xenon tetrafluoride · One of the first noble gas compounds ever made, in 1962.
The XeF4 Lewis structure has 36 valence electrons, drawn as four Xe–F bonds, with 14 lone pairs in total. The central Xe is sp3d2 hybridized, which makes it a square planar molecule with a bond angle of 90 degrees. XeF4 is nonpolar: the bond dipoles and lone pairs are arranged symmetrically, so the vectors cancel and the molecule has no net dipole.
- 36 valence e−
- square planar
- 90° bond angle
- sp3d2
- nonpolar
Calculated properties
| Total valence electrons | 36 |
|---|---|
| Bonding electrons | 8 (4 shared pairs) |
| Nonbonding electrons | 28 (14 lone pairs) |
| Lone pairs on Xe | 2 |
| Electron domains (steric number) | 6 |
| VSEPR notation | AX4E2 |
| Electron geometry | octahedral |
| Molecular geometry | square planar |
| Bond angle | 90° |
| Hybridization | sp3d2 |
| Polarity | nonpolar |
| Formal charges | all zero |
| Resonance structures | none |
| Molar mass | 207.282 g/mol |
How to draw the XeF4 Lewis structure
-
Count the valence electrons
Add up the outer-shell electrons every atom brings. That total is the budget for the whole structure - every line and every dot has to come out of it, and nothing may be added.
8 (Xe) + 4 x 7 (F) = 36 valence electrons -
Choose the central atom
Xe is the least electronegative atom here, so it takes the centre. Hydrogen is never central: it can only form one bond.
-
Join everything with single bonds first
Every connection starts as one shared pair. Draw them all before worrying about double bonds - the arithmetic in the next step is what tells you where the double bonds have to go.
4 bonds x 2 = 8 electrons used, 28 left -
Work out how far short you are
Add up what every atom still needs to fill its shell - eight electrons for most atoms, two for hydrogen - minus what its single bonds already give it. Compare that with the electrons you have left. The difference decides everything that follows.
needs 24, has 28, 4 to spare -
Park the spare electrons on the central atom
There are 4 electrons more than the outer atoms can use. They become 2 extra lone pairs on Xe, which is in period 5 and can hold more than eight electrons. A period-2 atom could not do this.
12 electrons around Xe -
Fill in the lone pairs
Every electron not in a bond sits as a lone pair on an atom. Each atom takes exactly what it needs to finish its shell - there is no choice left at this point.
Xe: 2, F1: 3, F2: 3, F3: 3, F4: 3 (28 electrons) -
Check the central atom
Xe ends up with 12 electrons, an expanded octet. Only period 3 and below can do this.
Xe: 8 bonding + 4 nonbonding = 12 -
Check the formal charges
Formal charge is valence electrons, minus lone-pair electrons, minus the number of bonds. Every atom here comes out at zero, which is the sign of a good structure.
all formal charges = 0 -
Work out the shape
Count the electron domains on Xe: 4 bonded groups plus 2 lone pairs. A double or triple bond still counts as one domain, because it points in one direction. That gives octahedral electron geometry; ignore the lone pairs and the atoms themselves sit in a square planar arrangement. The two lone pairs sit opposite each other, above and below the plane, so the four bonds stay at a clean 90 degrees.
steric number 6 -> sp3d2 -> square planar, bond angle 90 -
Decide whether it is polar
The bond dipoles and lone pairs are arranged symmetrically, so the vectors cancel and the molecule has no net dipole.
dipoles cancel -> nonpolar
Is XeF4 polar or nonpolar?
XeF4 is nonpolar. The bond dipoles and lone pairs are arranged symmetrically, so the vectors cancel and the molecule has no net dipole.
| Bond | Electronegativity difference | Character |
|---|---|---|
| Xe–F | 1.38 | polar covalent |
Common questions
How many valence electrons does XeF4 have?
XeF4 has 36 valence electrons. 8 of them are in bonds and 28 sit in lone pairs.
What is the molecular geometry of XeF4?
XeF4 is a square planar molecule. The central Xe has 4 bonded groups and two lone pairs, a steric number of 6, which gives octahedral electron geometry and a square planar molecule.
What is the bond angle in XeF4?
The bond angle in XeF4 is 90 degrees. The two lone pairs sit opposite each other, above and below the plane, so the four bonds stay at a clean 90 degrees.
What is the hybridization of XeF4?
The central Xe in XeF4 is sp3d2 hybridized. Steric number 6 means 6 orbitals have to be mixed, which is exactly what sp3d2 gives you.
Is XeF4 polar or nonpolar?
XeF4 is nonpolar. The bond dipoles and lone pairs are arranged symmetrically, so the vectors cancel and the molecule has no net dipole.
Why does XeF4 break the octet rule?
The central atom has more than four bonded groups, so it has to hold more than eight electrons. Elements from period 3 downward can do this; period-2 elements like carbon, nitrogen and oxygen cannot.