Jonski potencijal anjona: geohemijski značaj i odgovarajuća podela anjona

Ionic potential of anions: geochemical importance and related divison of anions

Abstract

Ionic potential (IP), a parameter defined as the ratio of ionic charge and ionic radius (Cartledge 1928), has a long time an important application in geochemistry, but it is restricted only on cations. According IP 3 groups of cations are selected: soluble cations, elements of hiydrolizates, and soluble complex anions (Goldschmidt, 1934; 1937). The paper considers radii and ionic potential of anions as well as geochemical conditions of their appearing. According their position on an appropriate ionic charge (valence) - ionic radius diagram and geochemical characteristics, anions are divided into 3 groups. The groups are: (1) soluble anions, with IP <[0.8] /F^1-, Cl^1--, Br^1- and Cl^1-/; (2) anions o f reduzates, with IP from -0.8 to -1.2 /S^2-, Se^2-, and Te^2-/; and (3) anions o f uncommon anoxic systems, with IP >[1.2] /As^3-, Bi^3-, Sb^3-, N^3-, P^3-, C^4-- and Si^4-/. Geochemical characteristics of the groups indicate that IP of anions appears to be imporlant for explanation of behavior of related chemical elements in geochemical systems. That indicates that one can expect a wide application of IP of anions and the established division of anions in tlie geochemistry.