CHEMILUMINESCENCE IN THE SYSTEM ATOMIC SODIUM PLUS ATOMIC HYDROGEN

Abstract

When atomic sodium is diffused into a mixture of atomic and molecular hydrogen, a weak chemiluminescence is observed in the gas phase. Visible emission consists of the sodium D lines. The total intensity of the emission, ~5 × 10¹¹ photons/second, indicates that only one in 5 × 10⁴ of the sodium atoms entering the reaction vessel is involved in luminescent reaction. In order to account for the rapid fall-off in intensity of the flame away from the nozzle it is necessary to suppose that some non-luminescent reaction is removing sodium atoms in the gas phase. Preliminary experiments suggest that the non-luminescent reaction is Na + H + H₂ ^→ NaH + H₂, and the luminescent reaction either Na + Na + H ^→ NaH + Na* with collision yield 4 × 10⁻³ or Na + H + H ^→ H₂ + Na* with collision yield 1 × 10⁻⁵.