Resonant MPI spectrum of allyl radicals

摘要

A mass-selected, partially rotationally resolved, resonant multiphoton ionization spectrum of the allyl radical, C$-3$/H$- 5$/, is reported. Photoelectron spectroscopy, isotopic labelling, and rotational analysis establish that the band system corresponds to the 2$+2$/B$-1$/ $IMP 1$+2$/A$-2$/ transition, with an origin band at 248.15 nm. Spectral simulation indicates that the equilibrium CCC bond angle of the radical decreases from 124.6$DGR in the ground state to 117.5$DGR in the excited state.