- The first photoelectron spectra of triple-decker sandwich complexes are reported. The complexes CpV(,6-C6H6)VCp and CpV(,6-C6H3Me3)VCp have only 26 valence electrons. Comparison of the experimental results with molecular orbital calculations shows that the ground states have four unpaired electrons. The order of the upper valence electrons differs from that predicted by earlier extended-Hickel calculations. 1984, American Chemical Society. All rights reserved.