Calculation of sulfur isotope fractionation in sulfides
Calculation of sulfur isotope fractionation in sulfides
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DOI：
10.1016/j.gca.2005.12.015
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发表时间：
2006-04
影响因子：
5
通讯作者：
Yongbing Li;Jianming Liu
中科院分区：
文献类型：
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作者：
Yongbing Li;Jianming Liu
增量法已成功应用于计算硅酸盐、氧化物、碳酸盐和硫酸盐中氧的热力学同位素分馏因子。本文根据硫-金属键的化学特征和硫化物矿物的晶体特征，改进增量法计算硫化物中硫的热力学同位素分馏因子。为了近似硫化物的键强度，引入了一个新常数，称为马德隆常数。然后将增量法扩展到计算闪锌矿、黄铜矿、方铅矿、磁黄铁矿、绿铁矿、斑铜矿、立方石、硫化铜矿和紫铜矿的约化配分函数比，以及它们在0~1000℃温度范围内的同位素分馏因子。这9种矿物中34S富集顺序为：磁黄铁矿>绿铁矿>闪锌矿>黄铜矿>立方铜矿>硫化铜矿>斑铜矿>紫铜矿>方铅矿。我们改进的方法构成了计算具有地球化学意义的硫化物中硫的热力学同位素分馏因子的另一个模型。
The increment method has been successfully applied to calculate thermodynamic isotope fractionation factors of oxygen in silicates, oxides, carbonates, and sulfates. In this paper, we modified the increment method to calculate thermodynamic isotope fractionation factors of sulfur in sulfides, based on chemical features of sulfur–metal bonds and crystal features of sulfide minerals. To approximate the bond strength of sulfides, a new constant, known as the Madelung constant, was introduced. The increment method was then extended to calculate the reduced partition function ratios of sphalerite, chalcopyrite, galena, pyrrhotite, greenockite, bornite, cubanite, sulvanite, and violarite, as well as the isotope fractionation factors between them over the temperature range from 0 to 1000°C. The order of34S enrichment in these nine minerals is pyrrhotite > greenockite > sphalerite > chalcopyrite > cubanite > sulvanite > bornite > violarite > galena. Our improved method constitutes another model for calculating the thermodynamic isotope fractionation factors of sulfur in sulfides of geochemical interest.