Andrej Šmalc

On the synthesis of chlorine pentafluoride

Abstract The reaction between chlorine trifluoride and elemental fluorine was studied in order to find the optimal reaction conditions for the synthesis of chlorine pantafluoride. It has been found that nickel difluoride is a very effective catalyst for the mentioned reaction. The obtained results are expressed as space-time-yield of chlorine pentafluoride.

An examination of the possibility of the existence of xenon octafluoride

Abstract The possibility that xenon octafluoride might exist was first suggested in 1963. Later thermochemical and theoretical work indicated that there was a marginal chance that such a compound should be sufficiently stable to isolate. Our measurements of the temperature dependence of pressure in xenon-fluorine mixtures give F:Xe ratios of 6 for temperatures from 22 to 200°C and 260 to 350°C but those between 200 and 250°C are higher. It appears that the unexpectedly high absorption of fluorine cannot be accounted for by thermal expansion of the reaction vessel, the absorption of fluorine by the walls of the reaction vessel or the non-ideality of fluorine gas. Possibly association of xenon hexafluoride under high pressure or the existence of a higher fluoride of xenon could explain the observed effect. However, isolable quantities of xenon octafluoride were not obtained and no i.r. evidence for such a compound was observed.

Recent work in the photochemistry of xenon fluorides

Abstract Photochemical reactions in the system xenon-fluorine were studied in continuation of our work in this field. For this purpose a new type of sapphire- nickel photochemical reactor with much higher light efficiency was designed. Photochemical reactions between xenon, xenon difluoride or xenon tetrafluoride and fluorine in the gaseous as well as in the liquid state were investigated. Special emphasis was given to investigation of the photochemical dissociation of xenon hexafluoride. The influence of some reaction conditions, e.g. initial presence of reaction products, partial pressure of reactants etc., upon the course of the reaction will be discussed.