Interhalogen Compounds

Interhalogen compounds are binary compounds formed between different halogens. These compounds consist of two different halogen atoms and are classified based on their stoichiometry.

Types of Interhalogen Compounds

AX
AX₃
AX₅
AX₇

These are considered halides of the more electropositive halogen. The central atom 'A' must be more electropositive than the substituent halogen 'X'. For example, fluorine can never act as a central atom due to its highest electronegativity, while iodine can never act as a substituent.

Examples include:
ClF – Chlorine monofluoride
ICl₃ – Iodine trichloride

Bonding and Polarity

In interhalogen compounds, atoms are linked by covalent bonds, similar to how halogens bond among themselves. Due to a small electronegativity difference between the atoms, these bonds exhibit some polarity. Examples like ICl, ICl₃, and BrF₃ show partial ionic character.

Stability and Valency

Compounds with AX and AX₃ structures occur when the electronegativity difference is not very large. Higher valency compounds like AX₅ and AX₇ form when large halogen atoms such as iodine or bromine bond with smaller ones like fluorine. This is because more small atoms can fit around a larger central atom.

Interhalogen Compounds