SbF5 Lewis structure

SbF₅ (antimony pentafluoride) has one antimony atom and five fluorine atoms.

In the SbF₅ Lewis structure, there are five single bonds around the antimony atom, with five fluorine atoms attached to it, and on each fluorine atom, there are three lone pairs.

Alternative method: Lewis structure of SbF₅

Rough sketch

• First, determine the total number of valence electrons

In the periodic table, antimony lies in group 15, and fluorine lies in group 17.

Hence, antimony has five valence electrons and fluorine has seven valence electrons.

Since SbF₅ has one antimony atom and five fluorine atoms, so…

Valence electrons of one antimony atom = 5 × 1 = 5
Valence electrons of five fluorine atoms = 7 × 5 = 35

And the total valence electrons = 5 + 35 = 40

Learn how to find: Antimony valence electrons and Fluorine valence electrons

• Second, find the total electron pairs

We have a total of 40 valence electrons. And when we divide this value by two, we get the value of total electron pairs.

Total electron pairs = total valence electrons ÷ 2

So the total electron pairs = 40 ÷ 2 = 20

• Third, determine the central atom

We have to place the least electronegative atom at the center.

Since antimony is less electronegative than fluorine, assume that the central atom is antimony.

Therefore, place antimony in the center and fluorines on either side.

• And finally, draw the rough sketch

Lone pair

Here, we have a total of 20 electron pairs. And five Sb — F bonds are already marked. So we have to only mark the remaining fifteen electron pairs as lone pairs on the sketch.

Also remember that antimony is a period 5 element, so it can keep more than 8 electrons in its last shell. And fluorine is a period 2 element, so it can not keep more than 8 electrons in its last shell.

Always start to mark the lone pairs from outside atoms. Here, the outside atoms are fluorines.

So for each fluorine, there are three lone pairs, and for antimony, there is zero lone pair because all fifteen electron pairs are over.

Mark the lone pairs on the sketch as follows:

Formal charge

Use the following formula to calculate the formal charges on atoms:

Formal charge = valence electrons – nonbonding electrons – ½ bonding electrons

For antimony atom, formal charge = 5 – 0 – ½ (10) = 0

For each fluorine atom, formal charge = 7 – 6 – ½ (2) = 0

Here, both antimony and fluorine atoms do not have charges, so no need to mark the charges.

Final structure

The final structure of SbF₅ features a central antimony atom linked to five fluorine atoms through single covalent bonds. In this arrangement, the antimony atom utilizes an expanded valence shell to accommodate ten electrons, consisting of five bonding pairs with no lone pairs. Within this layout, each of the five fluorine atoms successfully satisfies the octet rule by retaining three lone pairs alongside its single shared bond. This configuration represents the most stable state for the molecule because it results in a formal charge of zero for every atom involved. Accordingly, this specific electronic distribution serves as the definitive and most accurate Lewis representation of antimony pentafluoride.

Next: C₂H₂Br₂ Lewis structure

External video

• How to Draw the Lewis Dot Structure for SbF5 – YouTube • Wayne Breslyn

External links

• https://lambdageeks.com/sbf5-lewis-structure/
• https://oneclass.com/homework-help/chemistry/6920909-sbf5-lewis-structure.en.html