Consider a KH molecule (MK=39, MH=1u). In this molecule, what happens to the rotational energy spacings of KH and KD if you replace the hydrogen with deuterium?
a) Rotational energy spacings increase for both
b) Rotational energy spacings decrease for both
c) Rotational energy spacings increase for KH and decrease for KD
d) Rotational energy spacings decrease for KH and increase for KD