Three- and two-photon absorption in HCl and DCl: identification of Ω=3 states and state interaction analysis

Two-dimensional (2+n) resonance enhanced multiphoton ionization of HCl: State interactions and photorupture channels via low-energy triplet Rydberg states

“…This corresponds to the smallest spacing between the rotational energy levels in the f 3 ⌬ 2 ͑vЈ =0͒ and the V 1 ⌺ + ͑vЈ =8͒ states for the same JЈ =5 value ͑see Table II͒, suggesting a near-resonance interaction between the two states. 12,15,22 This effect does not show as an enhanced normalized H 35 Cl + signal for the V 1 ⌺ + ← ←X 1 ⌺ + , ͑8,0͒ system ͓see Fig. 4͑b͔͒, however, underlining the interaction weakness.…”

“…12,15 Since the interactions here are too weak to show as line/level shifts ͑see discussion above͒, only the upper limits for ⌬͑⌬E͒ ͓i.e., ⌬͑⌬E͒ max ͔ based on variations in the line/level spacing can be estimated. From these, the upper limit values for W 12 for the near-resonance rotational levels ͑J res Ј ͒ ͑W 12 max ͑J res Ј ͒͒ and the W 12 Ј parameters ͑W 12 Ј max ͒ can be evaluated from Eqs.…”

“…[6][7][8][9][10][11][12][13][14][15] Relatively intense single-and multiphoton absorptions in conjunction with electron excitations as well as rich band structured spectra make the molecule ideal for fundamental studies. A large number of Rydberg states, several low-lying repulsive states as well as the V͑ 1 ⌺ + ͒ ion-pair state have been identified.…”

“…7,8,[10][11][12]15 The perturbations appear either as line shifts 4,7,8,11,12,15 or as intensity and/or bandwidth alterations. 4,7,8,[10][11][12]15 Pronounced ion-pair to Rydberg state mixings are both observed experimentally 3,4,8,11,12,15,16 and predicted from theory. 16,17 Interactions between the V͑ 1 ⌺ + ͒ ion-pair state and the E͑ 1 ⌺ + ͒ state are found to be particularly strong and to exhibit nontrivial rotational, vibrational, and electron spectroscopy.…”

Two-dimensional (2+n) REMPI of HCl: Observation and characterisation of a new Rydberg state

“…Furthermore, Tilford et al reported 3 P states [6] and Ginter and Ginter have reported a 1 R À state [7] using single photon excitations. More recently our group reported observations of U states using (3 + 1) REMPI [8,9].…”