The occurrence forms and mechanisms of Zn in cerussite: Based on LA-ICP-MS and first principles

Abstract

This study aims to elucidate the occurrence mechanism of Zn in cerussite (PbCO₃) and to provide fundamental insights into zinc’s solid-phase behavior in mineral systems. The occurrence forms of Zn are studied by LA-ICP-MS tests and density functional theory (DFT) calculations, with a simplified model assuming Zn²⁺ as the primary species. The results indicate that the occurrence of Zn in cerussite primarily occurs through an ion-exchange mechanism on surface, not dominated by isomorphism or interstitial atoms. It is a good explanation of why Zn is mainly distributed on the growth surface of cerussite in LA-ICP-MS tests. Although the calculations do not consider more complex physicochemical conditions, the proposed model provides a new perspective for elucidating the occurrence mechanism of Zn in cerussite. By combining DFT calculations and LA-ICP-MS experimental data, we have revealed the interaction patterns between Zn and the mineral surface, Zn mainly has strong adsorption interaction with O on the surface. This study bridges the gap between theoretical simulations and geochemical observations, it may clarify the occurrence of Zn in carbonate-rich environments. Future work could focus on improving the adsorption model’s accuracy by incorporating solvent effects, temperature dependence, and more complex species behavior. These advancements are expected to deepen mechanistic insights into zinc mineralization.