Theoretical and Experimental Fractionation Studies of Chloride and Bromide Isotopes

Abstract

Diffusion probably is the most well known and most well understood process that is responsible for variations in chlorine and bromine isotope compositions. Molecular diffusion is the process in which matter is transported from one part of a system to another as a result of arbitrary molecular movements (Crank in The mathematics of diffusion. Oxford University Press, London, p 347, 1956). It was first described by Fick (Ann Phys 170:59–86, 1855). This work is now referred to as Fick’s First and Second Laws, and was published even before quantitative experimental measurements had ever been done. Lindemann (Proc Royal Soc London. Series A 99:102–104, 1921) already realised that, due to the mass difference of isotopes from a single element isotopes could theoretically be separated electrolytically. The first study where fractionation due to diffusion of chlorine isotopes was studied was already done in the 1940s (Madorsky and Straus in J Res Nat Bur Stand 38:185–189, 1947) and several more studies have been applied since then going from theoretical, experimental and field studies.