墨铜矿的穆斯堡尔谱特征

Characteristics of Messbauer Spectra of Valleriite

墨铜矿是典型的异类矿物结构基元层间层矿物．在其结构中，Ｆｅ可占据硫化物层中四次配位和氢氧化物层中六次配位两种位置。本文通过穆斯堡尔谱研究，确定了墨铜矿的穆斯堡尔谱谱型，并认为高自旋的Ｆｅ２＋占据四次配位位置，与Ｃｕ离子一起可能呈无序占位，配位环境的对称性较低，谱参数为：ＩＳ＝０．４２－０．４８ｍｍ／ｓ、ＱＳ＝０．８１－１．２８ｍｍ／ｓ及Ｈｉ约为２４０ＫＯｅ；低自旋的Ｆｅ３＋占据六配位位置，ＩＳ值为０．３２－０．３６ｍｍ／ｓ、ＱＳ值为０．４４－０．５９ｍｍ／ｓ。

Valleriite is a typical interstratified mineral with its basic structural sheet in different classes. In its structure, iron ions may occupy two sites: tetrahedral site in sulfide sheet and octahedral site in hydroxide sheet. On the basis of the Mssbauer data obtained at room temperature, the spectral pattern and Mssbauer parameters of valleriite are obtained. The results suggest that high-spin Fe2+ is present in tetrahedral site with isomer shift (IS) of 0. 42-0. 48 mm/s and quadrupole splitting (QS) of 0. 81- 1. 28 mm/s, also with a random distribution at this site and lower symmetry of coordination environment;low-spin Fe3+ is present in octahedral site with IS of 0. 32-0. 36 mm/s and QS of 0. 44- 0. 59 mm/s.