Rovibrational-state selected photoionization of acetylene by the two-color IR + VUV scheme: observation of rotationally resolved Rydberg transitions

摘要

[[abstract]]We have demonstrated a rovibrational-state-selected photoionization experiment using an IR laser and high-resolution VUV-synchrotron radiation. The VUV photoionization of acetylene [C2H2(X˜ 1Σg+;ν3=1,J′=8   or   10)] prepared by IR excitation reveals three strong autoionizing Rydberg series converging to C2H2+(X˜ 2Πu;ν3+=1) with little ion background interference. Rotational transitions resolved for the Rydberg states provide an estimate of ≈1.8  ps for their lifetimes. This experiment opens the way for state-selective photoionization studies of polyatomic molecules using VUV-synchrotron radiation.