Vibrationally resolved photoelectron spectroscopy of the first row transition metal and C_3 clusters:MC_3~-(M=Sc,V,Cr,Mn,Fe,Co,and Ni)

摘要

We report photoelectron spectra of the MC_3~- clusters for M=Sc, V,Cr,Mn,Fe,Co,and Ni at two photon energies, 355 and 266 nm. Vibrational strucutre is resolved for the grounjd and excited state detachment transitions for all the clusters except for CoC_3~- and NiC_3~-. Electron affinity (EA) and vibrational frequencies for the MC_3 clusters are obtained. Complicated low-lying excited state features are observed for all the species. We find that the trend of the EA across the 3d series for the MC_3 clusters is similar to that of the MC_2 species. The vibrational frequency is found to increase from ScC_3 to TiC_3 and then decreases monotonically to the right of the 3d series. Preliminary density functional theory calculations are performed on all the MC_3 and MC_3~- clusters at several initial geometries and spin multiplicities. We find that the ground states of all the MC_3 and MC_3~- species have C_(2v) ring structures. The calculated M-C stretching frequency for all the MC_3 species is in good agreement with the experimental measurement, lending credence to the obtained C_(2v) structure.