Sidney Toby

Chemiluminescence in the gas-phase reaction between ozone and allene

Abstract The reaction between ozone and allene is accompanied by chemiluminescence extending from 325–525 nm. The well-resolved spectrum obtained is that of electronically excited formaldehyde (1A2). Unlike the case for mono-olefins studied by Finlayson and Pitts [1] no other emission was seen.

Chemiluminescence in the gas phase reaction between tetrakis (dimethylamino)ethylene and oxygen

Abstract Chemiluminescence from the reaction between tetrakis(dimethylamino)ethylene (TMAE) and oxygen in the gas phase is reported. It was found that the spectrum of the emitted light showed a broad band with a maximum at about 500 nm, which is similar to what has been reported from liquid phase work and similar to the fluorescence spectrum of pure TMAE. The liquid phase chemiluminescence is well known and has been postulated to occur via a proton donor leading to an ionic complex. If the same emitter is formed in the gas phase, the reaction probably occurs via free radicals. The emission in the range 10-45 °C was studied as a function of pressures of oxygen and TMAE. The effect of added hydroxylic compounds in the gas phase was to increase the emitted intensity but their presence was not necessary for chemiluminiscence, contrary to what has been claimed for liquid phase work. The emission was very long lived for a gas phase reaction in a closed system and was measurable after about 30 min under some conditions. Both peak and integrated light intensities decreased mardedly as the temperature was raised at the same reactant concentrations and were very weak above 45 °C. A mechanism is postulated which accounts for the behavior of the light emission and which was satisfactorily computer simulated.

A molality-molarity paradox?

The author points out that there seems no obvious reason why molality could not equal molarity in a solution whose density is less than unity.