UPS study of intramolecular interactions

Abstract

HeI photoelectron spectra (UPS) of pyrazabole and cubane-1,4-dicarboxylic acid dimethyl ester were recorded and analyzed using semi-empirical calculations. The efficiency of BH2 fragment in relaying interactions between pyrazole rings was determined. The cubane ester was studied because of possible through-bond interactions between carboxyl groups relayed via the rigid cubane skeleton. The energies of orbitals associated with COOMe group fall within the energy level gap between t2g+t2u and eg manifolds in cubane and it is interesting to determine which mechanism is operational for COOMe-COOMe interactions.