Nuclear volume effects in equilibrium stable isotope fractionations of mercury, thallium and lead

• DOI: 10.1038/srep12626
• Publication Date: 2015-07-30T09:15:29Z
• Authors: Sha Yang; Yun Liu
• Keywords: Mass-independent fractionation; Mercury; TRACER; Thallium

Abstract The nuclear volume effects (NVEs) of Hg, Tl and Pb isotope systems are investigated with careful evaluation on quantum relativistic via the Dirac’s formalism full-electron wave function. Equilibrium 202 Hg/ 198 205 Tl/ 203 Tl, 207 Pb/ 206 208 fractionations found can be up to 3.61‰, 2.54‰, 1.48‰ 3.72‰ at room temperature, respectively, larger than predicted by classical mass-dependent theory. Moreover, NVE cause mass-independent (MIF) for odd-mass isotopes even-mass isotopes. plot "Equation missing"<!-- image only, no MathML or LaTex -->vs. --> Hg-bearing species falls into a straight line slope 1.66, which is close previous experimental results. For first time, 4+ -bearing enrich heavier 2+ surprising extent, e.g., enrichment 4.34‰ in terms due their NVEs opposite directions. In contrast, among trivial. Therefore, large fractionation changes provide potential new tracer redox conditions young closed geologic systems. magnitudes NVE-driven MIFs (i.e., -->) almost same but signs.