【摘要】 本文对产于我国山东的新矿物蒙山矿（Mathiasite）进行了晶体结构精测。蒙山矿的晶体化学式为:（K、Ca、Sr）（Ti、cr、Fe、Mg、Zr）₂₁O₃₈,三方晶系,空间群R,晶胞参数:a_o=10.3722,c_o=20.7161（六方定向）,a_R=9.1403,a=69.187°（菱面体定向）。应用RASA-5RP自动转靶四圆单晶衍射仪,对蒙山矿收集了独立的1554个衍射强度。经结构解析和修正,求得了晶体中各原子的坐标、温度因子、占位度。并计算了原子的间距和键角。结构修正的偏离因子: R=0.047。蒙山矿产于金伯利岩中,形成于高温高压下。通过结构测定,确定了该矿物中Ti、Cr、Mg、K等元素的配位形式,特别是查明了Zr在这种以Ti为主的复杂氧化物中有独立的结晶学位置,并有缺席现象。以上研究成果丰富了金伯利岩中金属副矿物的矿物学和晶体化学内容。更多还原

【Abstract】 The crystal structure of mathiasite, a new mineral from Shandong province, has been determined, and the crystal chemical formula is written as（K, Ca） （Ti, Cr, Fe, Mg, Zr）₂₁O₃₈. The mineral belongs to trigonal system having space group of R（?）, with its cell parameters being a=10.3722, c=20.7161, a_R=9.1403 and α=69.137° 1554 independent diffraction data were collected on RASA-5RP auto-fourcircle single crystal diffractometer; coordinates, temperature factors and site occupancies for all atoms were obtained and refined; atomic distances and angles were calculated. The final deviation factor R is 0.047.Mathiasite occurs in kimberlite and must have formed under high temperature and pressure. Through the determination of its structure, the coordination about such atoms as Ti, Cr, Mg and K, especially the coordination about Zr atom in the complex oxide dominated by Ti, has been revealed.This research contributes to the mineralogy and crystal chemistry of accessory metallic minerals in kimberlite.更多还原