# Thermal stability of interhalogen compounds

I am striving over the question that what would be the stability order of the following interhalogen compounds : $\ce{ClF3, BrF3}$ and $\ce{IF3}$.

• One probable answer I got is that stability of interhalogen compounds decreases as the size of central atom decreases due to electronegativity difference. Hence, the stability order should be $\ce{IF3} > \ce{BrF3} > \ce{ClF3}$.

Is the above mentioned logic correct? Can someone please elaborate?

• Stable with respect to what?
– DHMO
Oct 12 '16 at 12:52
• Thermal stability Oct 12 '16 at 13:33

More electronegativity difference generally gives you stronger bonds, therefore higher thermal stability (i.e. you need to put in more energy to break them). Also, there are 2 lone pairs on the central atom and 3 on each F. Thus, interhalogen compounds of this type with larger central atom would experience less electron pair repulsion. So, I believe that the correct order is $\ce{IF3>BrF3>ClF3}$ as you suggested.