A molecule consist of two atoms each of mass 'm' and separated by a distance
of 'd' If 'K' is the average rotational K.E. of the molecule at particular temperature
then its angular frequency is….
The M.I of the molecule = $ M \left( { d \over 2 } \right) + m \left( { d \over 2} \right)^2 $ $ I = 2m \left( { d^2 \over 4 } \right) = { md^2 \over 2 } $ The Rotational K.E. of the moldule $ (K) = { 1 \over 2} I \omega^2 $ $ \omega = \sqrt { 2K \over I } $