PFI-ZEKE SPECTROSCOPY OF ALUMINUM IMIDAZOLE AND PYRIMIDINE COMPLEXES

Abstract

Aluminum complexes of imidazole (1,3-C${3}$H${4}$N${2}$) and pyrimidine (1,3-C${4}$H${4}$N${2}$) are produced by interactions between laser-ablated aluminum atoms with imidazole or pyrimidine vapor in supersonic molecular beams and studied by pulsed field ionization zero electron kinetic energy spectroscopy. The ionization energies of Al-imidazole and -pyrimidine are measured to be 35344(5) and 44182(6) cm$^{-1}$, and the Al$^+$-imidazole and -pyrimidine stretching frequencies are 308 and 262 cm$^{-1}$, respectively. In addition, an Al$^+$-imidazole in-plane bending mode is determined to be 125 cm$^{-1}$. Preliminary spectral analysis shows that aluminum atom or ion binds with single nitrogen of the ligand, and both complexes are in $C_s$ symmetry.