Photoelectron spectra of acrylonitrile cluster anions, (AN)n- (2≤n≤8), were measured at photon energies of 2.33 and 3.49 eV. A broad peak in each spectrum was approximated by a Gaussian function which reflects the amplitude of the vibrational wavefunction for the ground state of the anion. The measured vertical detachment energy decreases abruptly from 2.1 eV at n = 2 to 0.9 eV at n = 3 and increases gradually. This n-dependence is explained by the anion structure that the anion with n ≤ 5 is composed of a polymerized cyclic trimer anion, (AN)3-, and AN, while that with n ≥ 6 contains a polymerized cyclic trimer unit, (AN)3, in addition to (AN)3- and AN. The dimer anion, (AN)2-, should have an acyclic geometry.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)
- Physical and Theoretical Chemistry