Figure 4: Dispersion law Δ E=ΔE(ω).
From: Site-selective photoemission from delocalized valence shells induced by molecular rotation
It describes the dependence of the electron energy on the angular velocity 
in the ground state, where 
and 
, respectively ,are the parallel and the perpendicular components of ω with respect to the recoil angular momentum j=[RH × k]. This dispersion law, responsible for the formation of the rotational envelope of the individual vibrational sub-states (see Methods section), is very sensitive to the change in the moment of inertia during photoionization. It is qualitatively different for (a) β=0 and for (b) β≠0 (see text). The position of the bottom of the paraboloid is (ΔE=−42 meV, 
, 
) for β=−0.5, while the position of the top of the paraboloid is (ΔE=124 meV, 
, 
) for β=0.5. (c) Rotational Doppler broadening D (FWHM), and shift Δ, caused by the rotational recoil effect, computed as the width and shift of the spectrum (1) for the hydrogen atom in room temperature (T=300 K) HCl.
