摘要
变生使矿物的物理、化学性质发生显著变化。本文着重研究变生对锆石阴极射线发光谱的影响。为此,对若干锆石样品进行了X射线粉晶分析,差热分析和室温阴极射线发光谱测量。衍射和差热分析结果表明,这些样品具有不同的变生程度,有些样品已完全变生,有些部分变生,有些则是晶质的。所研究样品的阴极射线发光谱中,主要的发光谱线均来源于Dy^(3+)离子的~4F9/2→~6H_(13/2)和~4F_(9/2)→~6H_(15/2)跃迁。与晶质锆石相比,变生锆石发光谱线的强度降低、宽度增加表明在变生过程中,锆的局部环境发生畸变,无序程度增加。根据发光谱的特征,可以定性地估计锆石的变生程度。
Cathodoluminescence(CL) spectra of a suite of zircons were measured at room temperature. X-ray powder diffraction and thermal analyses indicate that they have undergone different degrees of metamictization, ranging from non-metamict to nearly completely metamict. The main luminescence lines of the samples studied are due to the ~4F_(9/2)→~6H_(13/2) and ~4F_(9/2)→~6H_(15/2) transitions of Dy^(3+) ions substituting for Zr^(4+). Results of the present work show that metamictization has profound influence on the CL spectrum. With increasing degree of metamictization, intensities of the luminescence lines tend to decrease and the line widths to increase, indicating that the distortion of the Zr coordination polyhedra occurred and the disorder in the second and farther atomic shells around Zr increased durnig the process of metamictizstion.
出处
《矿物学报》
CAS
CSCD
北大核心
1992年第4期323-328,共6页
Acta Mineralogica Sinica
基金
国家自然科学基金
关键词
锆石
变生
X射线衍射
差热分析
zircon
metamictization
X-ray powder diffraction
DTA
cathodoluminescence spectrum
