For a molecule such as CO, which has a permanent electric dipole moment, radiative transitions obeying the selection rule Δℓ = ±1 between two rotational energy levels of the same vibrational level are allowed. (That is, the selection rule Δn = ±1 does not hold.)

(a) Find the moment of inertia of CO and calculate the characteristic rotational energy E_0r (in eV).

(b) Make an energy level diagram for the rotational levels for ℓ = 0 to ℓ = 5 for some vibrational level. Label the energies in electron volts starting with E = 0 for ℓ = 0.

(c) Indicate on your diagram transitions that obey Δℓ = -1 and calculate the energy of the photon emitted

(d) Find the wavelength of the photons emitted for each transition in (c). In what region of the electromagnetic spectrum are these photons?