BEAM-GAS CHEMILUMINESCENCE OF SmO, EuO, SmF, AND EuF

Abstract

Studies are made of the visible chemiluminescence resulting from the reaction of an atomic beam of Sm or Eu with $O_{3}$, $N_{2}$O, $NO_{2}$ and $F_{2}$ under single-collision conditions ($\sim$ 10$^{-4}$ Torr). We report here the progress on the analysis of the spectra of SmO, EuO, SmF, and EuF, The absolute photon yield for the brightest reaction, Sm + $F_{2}$, is determined to be $\sim$ 1%. From the short wavelength cutoff of the chemiluminescent spectra, the following lower bounds to the ground state dissociation energies are obtained; $D_{0}^{0}$(SmO) $\geq$ 135.5 $\pm$ 0.7 kcal/mole, $D_{0}^{0}$(EuO) $\geq$ 131.4 $\pm$ 0.7 kcal/mole, $D_{0}^{0}$(SmF) $\geq$ 126.6 $\pm$ 2.1 kcal/mole, and $D_{0}^{0}$(EuF) $\geq$ 129.6 $\pm$ 2.1 kcal/mole.