Fig. 2: Spectroscopic characterization of the internalrotor vibrational progression bands.
From: Tracking the structural change of the predissociating molecule near the transition state
(a) The DR3PI spectrum was recorded at the IR photon energy of 2984.0 cm−1. Red-shaded areas depict the internal rotor levels with the internal rotation quantum number of m = 8, 9, or 10 anchored at the S1 zero-point level excited from the S0’ ( J’,Ka’) = (2,1) intermediate state. The experimental spectrum simulated using (b) the fixed molecular rotational constant (AF = 4.93 cm−1) or (c) the energy-dependent values (AF = 4.93, 4.77 or 4.52 for m = 8, 9, or 10, respectively) is given. (d) The m-dependent energies of internal rotor bands observed in the DR3PI spectrum (black circles), showing the systematic deviation from those from the simulations with AF = 4.93 cm−1 (red stars) for high m levels. Source data are provided as a Source Data file.
