碱土-铈氟碳酸盐矿物晶体结构中的无序堆垛和交生

用晶格象技术研究了同时含有钙和钡的铈氟碳酸盐矿物,发现这类矿物的晶体是由不同组分的钙-铈氟碳酸盐矿物和不同组分的钡-铈氟碳酸盐矿物单层无序堆垛而成,在百埃数量级的范围内,观察到不同组分钙-铈氟碳酸盐矿物的交生现象,由此提出伦琴钙铈矿可能有一种新的多型体。研究结果显示了晶格象技术直接观察这类矿物晶体结构的优越性。关键词：

INTERGROWTH AND DISORDER STACKING IN THE CRYSTAL STRUCTURE OF ALKALINE-EARTH-CERIUM FLUOROCARBONATE MINERALS

The cerium fluorocarbonate minerals containing both calcium and barium have been studied by the lattice imaging technique. It has been found that the crystal structure of such minerals are formed by stacking at random along the direction c layers of various barium-Cerium as well as calcium-cerium fluorocarbonate minerals. The inter-growth of some calcium-cerium fluorocarbonate minerals with different composition has been observed in the range of several angstrons. A possible new polytype in Roentgenite has been proposed. The results show the advantage of the lattice imaging technique in direct observation of the crystal structure of such minerals.