发表机构
1 IMPMC, Universit\'e Paris VI et VII, CNRS, IPGP, 4 Place Jussieu, 75252, Paris cedex 05, France 2 IRD -UMR CEREGE , Europole M\'editerran\'een de l'Arbois, BP 80 , 13545 Aix en Provence cedex, France
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究通过第一性原理密度泛函理论计算多种硅酸盐的硅、氧同位素分馏因子，分析其与矿物成分的关系，发现硅分馏与阳离子含量相关，氧分馏特性可为硅分馏研究提供参考。
AI 中文摘要
采用第一性原理方法计算了选定硅酸盐（石英、顽火辉石、镁橄榄石、利蛇纹石、高岭石）中氧和硅的同位素分馏因子。氧的理论计算结果与实验值吻合良好；对于硅，本文讨论了其平衡分馏因子与已有估算值的一致性及差异。研究分析了硅分馏因子与氧分馏因子、硅酸盐聚合度及化学成分之间的关系，未证实此前提出的与矿物聚合度相关的结论，但计算表明硅分馏依赖于矿物的阳离子含量，其规律与氧类似，因此氧的分馏特性可为硅分馏行为提供一定的见解。
英文摘要
Isotopic fractionation factors for oxygen and silicon in selected silicates (quartz, enstatite, forsterite, lizardite, kaolinite) have been calculated using first-principles methods. Good agreement between theory and experiment is obtained in the case of oxygen. In the case of silicon, agreement and differences with existing estimates of equilibrium fractionation factors are discussed. The relationships between silicon fractionation factors and oxygen fractionation factors, silicate polymerization degree and chemical composition is studied. The previously stated relationship with the polymerization degree of the mineral is not confirmed. Nevertheless, our calculation suggests that silicon fractionation depends on the cationic content of the mineral, in a way similar to oxygen. Oxygen fractionation properties could thus provide some insights on silicon fractionation behavior.
Journal refChemical Geology, 2009, 258 (1-2), pp.28-37
