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橄榄石是地壳和上地幔最重要的造岩矿物之一,在地球过渡带的高温高压条件下,它可以转变为具有尖晶石结构的尖晶橄榄石.以往曾对尖晶橄榄石及其形成条件进行了不少的研究.早期的研究表明,尖晶橄榄石γ-Fe_2SiO_4和Ni_2SiO_4以及Co_2SiO_4具有相似的晶体结构,有少量Si原子(2%～8%)占据左八面体位置上.后来,傅平秋等使用X射线衍射和M(?)ssbauer效应方法发现,27.5%的Si原子占据在所测高温高压下合成的铁尖晶橄榄石的八面体位置上.我们使用M(?)ssbauer效应方法,对5个在高温高压下合成的铁尖品橄榄石进行了研究,发现在铁尖晶橄榄石中次近邻效应的存在,并给出了Fe和Si离子在铁尖晶橄榄石中的占位.
Peridot is one of the most important rock-forming minerals in the crust and upper mantle under the conditions of high temperature and high pressure in the transition zone of the Earth, which can be transformed into spinel with spinel structure .In the past, Forming conditions have been studied.It has been shown in earlier studies that the spinel olivine γ-Fe 2 SiO 4, Ni 2 SiO 4 and Co 2 SiO 4 have similar crystal structures with a small amount of Si atoms (2% -8%) occupying the left octahedral position , And Fu Pingqiu et al. Found that 27.5% of the Si atoms occupy the octahedral sites of the iron spinel olivine synthesized under the conditions of high temperature and high pressure using the X-ray diffraction and M (?) Ssbauer effect method. We used the M? Ssbauer effect Method, five high-iron-tip olivines synthesized at high temperature and high pressure were studied. It was found that the secondary nearest neighbor effect was present in the iron spinel olivine. The presence of Fe and Si ions in the iron spinel olivine Placeholder.