Knowledge Bank

The Al and Ga complexes were produced by reactions of laser-vaporized metal atoms with piperidine $(C5H11N)$ and characterized by pulsed field ionization-zero electron kinetic energy (PFI-ZEKE) spectroscopy. For $Al-C5H11N$, the adiabatic ionization potential was measured to be $37060cm-1$, and vibrational frequencies were determined for the $Al+-N$ stretching $(238cm-1),Al+/Al-N-C$ bending $(84/105cm-1)$ and piperidine-based vibrations (300 and $464cm-1$). By comparing the ZEKE measurements with ab initio calculations, the neutral and ionic aluminum complexes were determined to be in $Cs$ symmetry with Al binding to the nitrogen of the chair-like piperidine ring. For the gallium complex, the ZEKE spectrum shows an ionization potential of $37529cm-1$, a $Ga+-N$ stretching frequency of $176cm-1$ and a $Ga+-N-C$ bending frequency of $70cm-1$.