The Growth and Crystallographic Properties of Calcium Fluor‐ and Chlorapatite Crystals
The Growth and Crystallographic Properties of Calcium Fluor‐ and Chlorapatite Crystals
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DOI：
10.1149/1.2426512
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发表时间：
1967
影响因子：
3.9
通讯作者：
J. Prener
中科院分区：
文献类型：
--
作者：
J. Prener
本文报道了在熔融CaCl_2或CaF_3中缓慢冷却多晶磷灰石溶液，生长出化学计量比的Cas（PO_4）_3F和Cas（PO_4）_3Cl晶体。虽然氟磷灰石是六方晶系，但光学和X射线观测表明Cas（PO 4）3C 1具有单斜晶系P21/B空间群。这种化合物的所有晶体都是高度孪晶的。在约200 ° C时，发生向六方相（P6 Jm）的转变。CaCl的损失，从晶体中分离的F离子导致六方相的稳定化，而在低浓度下，F离子杂质具有相反的效果。钙磷灰石[Cas（PO_4）_sX; X= F，C_1，OH]是一类重要的天然和合成化合物。氟磷灰石是磷的主要矿石，羟基磷灰石构成所有动物骨骼和牙齿的矿物部分，混合的氟氯磷灰石构成荧光灯中主要磷成分的基础。这些化合物的结构，光学和其他重要性质可以最好地使用高质量的单晶来确定和研究。本文的第一部分描述了溶液生长法用于获得相当大的，化学计量的氟磷灰石和氯磷灰石晶体。最近，Young和E1-Liott（1）在一些初步的实验中发现，通过在蒸汽中加热，可以将我们从溶液中生长的氯磷灰石晶体（但不是天然矿物氯磷灰石）转化为羟基磷灰石的单晶。它们只含有原始C1的6%。因此，这是第一次，这种生物学上重要的材料的大晶体可能成为可用于研究。从溶液中生长的氟磷灰石晶体已用于X射线照射下色心形成的光学和EPR研究（2）。
Stoichiometric crystals of Cas (PO4) sF and Cas (PO4) 3C1 were grown by slowly cooling solutions of the polycrystalline apatites in fused CaCI2 or CaF~. While fluorapatite is hexagonal, optical and x-ray observations indicate that Cas (PO4) 3C1 has a monoclinic P21/b space group. All crystals of this compound are highly twinned. At about 200~ a transition to a hexagonal phase (P6Jm) occurs. Loss of CaCI., from the crystals leads to a stabilization of the hexagonal phase whereas at low concentrations F ion impurities have the opposite effect. Some previous observations on the luminescence of Cas (PO4) 3-x (MnO4) xC1 can now be understood in terms of the lower symmetry structure.The calcium apatites [Cas (PO4) sX; X= F, C1, OH] form an important class of natural and synthetic compounds. Fluorapatite is the major ore of phosphorous, hydroxyapatite makes up the mineral portion of bones and teeth in all animals, and the mixed fluorchlorapatites constitute the base for the major phosphor component in fluorescent lamps. Structural, optical, and other significant properties of these compounds can best be determined and studied using single crystals of good quality. The first part of this paper describes the solution growth methods used for obtaining fairly large, stoichiometric crystals of both fluor-and chlorapatite. Recently Young and E1-liott (1) in some preliminary experiments have found it possible, by heating in steam, to convert the crystals of chlorapatite grown by us from solution (but not natural mineral chlorapatite) into single crystals of hydroxyapatite. These contained only 6% of the original C1. Thus for the first time, large crystals of this biologically important material may become available for study. The fluorapatite crystals grown from solution have been used in optical and EPR studies of color center formation on x-ray irradiation (2).