IF6+ Lewis Structure & Characteristics (11 Important Facts)

IF6+ is an interhalogen compound formed between two halogen atoms, I and F. It is a polyatomic molecule with molecular weight of 240.895 g/mol. Let us discuss more facts about IF6+.

IF6+ is a polyhalogen ion with six F atoms and one I atom connected to each other. Interhalogen compounds are highly important as catalysts in many nuclear reactions, as solvents. They have low heat of fusion and are essentially diamagnetic. IF6+ is an interhalogen cation and reactivity is similar to I and F.

IF6+ undergoes hydrolysis easily due to the difference in size between I and F. Let us study more properties of IF6+ like bond angle, polarity, covalency and lewis structure.

How to draw lewis structure?

Lewis structure of a molecule describes the skeletal structure and electronic distribution of bonding and non-bonding electrons. Let us draw the following lewis steps.

Calculating the total valence electrons

The most important deciding factor for lewis structure is counting the total available valence electrons. Iodine and Fluorine belong to the halogen series of 17th group of the periodic table. There are 7 valence electrons in the outermost shell of each halogen atom.

7 halogen atoms with a + charge gives 48 valence electrons. The outer shell electronic configuration of F and I are 2s22p7 and 5s25p7.

Choosing the central atom

I is chosen as the central atom as I has lower electronegativity than F. The electronegativity of F and I are 3.98 and 2.66. The least electronegative atom has a tendency to share more electrons for bond formation easily. This results in easy bond formation.

Drawing the bond pairs

A single bond pair is assigned between each of the six I-F sets. This results in all the F atoms to fulfil their octet. Also, I expands its octet by accommodating electrons in its d subshell to form 6 bonds with F. In doing so, 12 valence electrons are used and only 36 valence electrons remain.

Assigning the lone pairs

The remaining valence electrons are assigned as lone pairs of electrons to each of the F atoms. Each F atom takes up 3 sets of lone pairs of electrons. Each lone pair has 2 electrons so all the remaining 36 valence electrons are used up. 6*(3*2)= 36 valence electrons where 6 = six F atoms.

if6 lewis logo
Stepwise construction of IF6+ lewis structure

IF6+ lewis structure shape

Shape of any molecule depends on factors like total bond pairs, electronegativity and size of the atoms in the molecule. Let us learn more about IF6+ shape below.

The shape of IF6+ is octahedral. The molecule has 6 bonding pairs in total. The presence of positive charge is responsible for the octahedral shape. If there had been a minus charge, it would have been distorted octahedral. The shape of IF6+ can be calculated using a simple formula.

  • Shape of IF6+ = [(Total valence electrons of the central atom + total number of connector atoms + Any negative charge – Any positive charge)/2] – Total lone pairs on central atom
  • Shape of IF6+ = [(7+6+0-1)/2] – 0 = 6
if6+ lewis structure
Octahedral shape of IF6+ lewis structure

IF6+ lewis structure formal charge

Formal charge of any molecule is the theoretical charge assigned to each atom in a molecule provided the electrons are shared equally in the bonds. Let us discuss in details.

The formal charge of IF6+ is +1 which has been calculated using the mathematical formula ‘Formal charge = (Number of valence electrons in a free atom of the element) – (Number of unshared electrons on the atom) – (Number of bonds to the atom)’.

  • Formal charge of I = 7-0-6 = +1
  • Formal charge of all the six F atoms = 7-6-1 = 0
  • The overall formal charge of IF6+ is +1 hence it is not neutral.

IF6+ lewis structure angle

Bond angle is the angle formed in a molecule with the central atom bond to nearby two connected atom bonds. Let us interpret the angle formed in IF6+.

The bond angle of IF6+ is 900. There are 6 bonding pairs in IF6+. All the six I-F bonds are arranged at 90 degree to avoid maximum repulsion among the bonding pairs. Further, I is larger in size and its connector atoms, F, have lone pairs of electrons. So, it is best suited when they are separated at that angle.

IF6+ lewis structure octet rule

Octet rule states that every atom tries to take up 8 electrons in its shell to gain maximum stability by adopting inert configuration. Let us check in details below.

IF6+ lewis structure follows octet rule. However, I takes up more than 8 electrons in its shell violating octet rule. This happens as I has expanded octet due to the presence of d shells which can take more electrons if required. The remaining F atoms cannot expand its octet.

F is the first element of group 17 with no d orbitals to take extra electron like I and so it takes up 8 electrons in its outermost shell.

IF6+ lewis structure lone pairs

Lone pairs of electrons are the unreacted pairs of electrons that do not participate in any chemical bond formation. Let us calculate the total lone pairs of IF6+.

The total lone pairs of electrons of IF6+ lewis structure is 18. Those 18 electron pairs do not contribute to the bonding pairs. All the F atoms are equivalent and each has 3 lone pairs of electrons. The central atom, I, does not have any lone pairs and all its valence electrons are used in bond formation.

Lone pairs can be calculated using Total valence electrons = Total bond pairs + Total lone pairs

IF6+ valence electrons

Valence electrons are the outermost loosely bounded electrons that can take part in bonding formation or stay as lone pairs. Let us discuss more in details below.

The valence electrons of IF6+ is 48. The valence electrons can be counted from the ground state electronic configuration of individual atoms. The participating atoms are I and F. The ground state of F and I are [Ne]2s22p7 and [Kr]4d105s25p7. The electrons in 2s, 2p, 5s and 5p are the valence electrons.

IF6+ hybridization

Hybridization is a process to obtain low energy and stable hybridized orbitals by mixing of atomic orbitals of all the atoms in a molecule. Let us check below.

The hybridization of IF6+ is sp3d2. The 5s, 5px, 5py, 5pz, 5dx2-y2 and 5dx2 subshells of I undergoes hybridization and overlaps with the 2p orbitals of all the F atoms. This results in all the outer shell electrons of I pair up with the six F atoms. The resulting molecular orbitals are identical in energy.

Is IF6+ polar or nonpolar?

Polar molecules have some dipole moments that can make them dissolved in polar solvents. Let us discuss the nature of IF6+ in details.

IF6+ is a non polar molecule due to its symmetrical nature. Since IF6+ takes up octahedral structure with all the bonds being equivalent, the bond dipole moments cancel each other. This results in zero dipole moment making it a non polar molecule. As such, it is soluble only in non polar solvents.

The non polar nature makes it unlikely to form dipole-dipole interaction with water molecules. The presence of the + charge somehow associates with ionic solvents.

Is IF6+ ionic or covalent?

Covalent molecules are formed between low electronegativity difference atoms and generally between non-metals. Let us study its relevant answer in details below.

IF6+ is a covalent molecule with slight ionic nature due to its plus positive charge that results in some association with other ionic molecules. It is a covalent molecule as it is formed between two non-metals, I and F with comparable electronegativity and difference less than 1.5.

So, as per Fajan’s rule of ionic molecule, it is a covalent molecule that can only dissolve properly in low ionic solvents due to its high polarization.

Is IF6+ soluble in water?

Solubility depends on factors like size, electronegativity, shape, electron pairs, lattice type and hydration energy, Let us check in details below.

IF6+ is not soluble in water. This is due to its non polar nature and shape which makes it insufficient to form dipoles in water solvent. IF6+ has high polarization and low dielectric constant. Furthermore, it has low hydration energy which is not sufficient to break the lattice of IF6+.

As a result, the lattice octahedral remains intact and do not dissolve in water in normal conditions.

Is IF6+ an electrolyte?

An electrolyte is a substance that consists of radicals which are anions and cations held together by electrostatic interactions. Let us check if IF6+ is an electrolyte or not.

IF6+ is not an electrolyte. The electrolytic nature is absent as it does not contain any positive cations and anions. The molecule as a whole is charge specific but do not possess radicals. It can conduct electricity in molten state but do not show electrolysis properties generally.


IF6+ is a charged interhalogen ion that is used as a fluorinating agents. It has low thermal stability due to size difference and low heat of fusion. It is covalent and non polar.

Also Read: