Bond dissosication energy question

[cake_is_a_lie]

Hello,
How can I calculate the bond dissociation energy for K⁺Br^- when I only know the the length of the bond?
Equation D₀ = D_e - 0.5hω does not help because I do not know ω and D_e. ω is the vibrational frequency of the bond.
Thank you for your advice beforehand.

 

[rexol]

isn't there an inorganic chemistry way to this.
I'm not really sure but i do remember finding energy of NaCl by i guess born haber cycle

 

[Borek]

If you assume its a purely ionic bond, you can calculate its energy just from electrostatic attraction. You know the initial distance, you known charges, just move atoms to infinity.