论文部分内容阅读
Daqingshanite,a new mineral recently discovered in China,is a kind of strontium-rare earth-bearing phosphate-carbonate.The ideal formula is:(Sr,Ca,Ba)_3RF(PO_4)(CO_3)_3. The mi-neral belongs to the trigonal system.The intensity data were collected with a single-crystal four-circle diffractometer.The lattice parameters are given as:a=10.058(±0.002);c=9.225(±0.003).Space group=R3m,Z=3.The crystal structure was solved by Patterson and electron densitysynthesis methods.The least-squares refinement led to a final conventional factor R=0.079.Crystal structural analysis shows that daqingshanite is of calcite-type structure and the or-dered model of cations is similar to that of huntite(Mg_3Ca(CO_3)_4).
Daqingshanite, a new mineral recently discovered in China, is a kind of strontium-rare earth-bearing phosphate-carbonate. The ideal formula is: (Sr, Ca, Ba) _3RF (PO_4) (CO_3) _3. to the trigonal system. The intensity data were collected with a single-crystal four-circle diffractometer. The lattice parameters are given as: a = 10.058 (± 0.002); c = 9.225 3. The crystal structure was solved by Patterson and electron density synthesis method. Least-squares refinement led to a final conventional factor R = 0.079. Crystal structural analysis shows that daqingshanite is of calcite-type structure and the or-dered model of cations is similar to that of huntite (Mg_3Ca (CO_3) _4).