Some Spectroscopic Reminiscences

We review a number of essentially spectroscopic problems in this personal account. The structure of high-temperature species remains a topic of considerable broad interest. The binary fluorides of essentially every element are stable as the isolated gas-phase molecular species. As such they provide a means of comparing bonding with the entire periodic table. The structural characterization of the binary fluorides, although still incomplete, has provided a considerable insight into a variety of bonding types.

The formation of molecules in the interstellar medium has been a model for abiotic synthesis of complex species. A kinetic model based upon ion­molecule reactions as the predominant reaction class appears to fit many of the observations, such as the polyatomic ion HCO⁺. The high abundance of carbon-chain compounds is attributed to the efficient formation of C⁺ by the reaction CO+He⁺ →C⁺ +O+He.

The spectroscopic characterization of weakly bonded species has led to a detailed knowledge of intermolecular potentials. The dynamics of molecular complexes has been frequently novel. In particular the concurrent breaking and making of weak bonds is observed in many species