JavaScript requeired.
Geochemical Journal
Geochemical Journal An open access journal for geochemistry
subscription
Published for geochemistry community from Geochemical Society of Japan.

Theoretical Calculation of Equilibrium Cadmium Isotope Fractionation Factors between Cadmium-bearing sulfides and aqueous solutions

Jixi Zhang, Renxue Shi
Geochemical Journal, Early Release (Accepted: 2022/10/13)

ABSTRACT

In this study, the equilibrium isotope fractionation factors between Cd-bearing aqueous solutions and minerals were predicted. The theoretical method used to calculate the Cd isotope fractionation factors is the first-principle quantum chemistry method (Cd: LANL2DZ, other atoms: 6-311+G(d, P)). Reduced partition function ratios (RPFRs) of Cd-bearing minerals (Greenockite and Sphalerite) were modeled by the method of the volume variable cluster model (VVCM). The theoretical method of “water-droplet method” is used to simulate the solvation effect of different Cd-bearing aqueous solutions. The results show that, in most cases, the Cd-bearing aqueous solutions are enriched in 114Cd relative to Greenockite. The Cd isotope fractionation factors between Cd-bearing aqueous solutions and Greenockite are in the range of 0.433-0.083 (100℃). And the Cd isotope fractionations between different Cd-bearing species are believed to be widespread. Cd isotope fractionation factors between different reservoirs are of great theoretical significance to many geochemical processes such as surficial geochemical process and ore-forming process. These theoretical parameters are studied systematically and carefully in this study.

KEYWORDS

Keywords: Cadmium isotope, Greenockite, Equilibrium isotope fractionation, VVCM, Cadmium cycle

All Issues

Current Issue:
Stats:
Impact Factor: 1.561
Geochemical Society of Japan

page top