稀土氨基酸配合物的研究(Ⅲ)——[Pr_2Cl_2(Gly)_4(H_2O)_6]·4Cl配合物的晶体结构

在水溶液中合成并培养了甘氨酸镨(或钐)配合物单晶,元素分析结果表明,化学式可用Ln(Gly)_2·Cl_3·3H_2O表示(Ln=Pr,Sm;Gly为甘氨酸)。X射线衍射测定结果,其结构式为(Pr_2Cl_2(Gly)_4(H_2O)_6]·4Cl,属单斜晶系,空间群P2_1/n,Z=2,晶胞参数为:a=1.0055(2),b=1.4619(3),c=1.0041(2)nm,β=102.09(1)°。每两个中心Pr~(3+)由两个甘氨酸羧基桥联成双核配合物。Pr~(3+)还与一个甘氨酸羧基双齿配位,再与3个O(H_2O)和一个Cl配位。Pr~(3+)的配位数为8。配位多面体由两个三角十二面体组成。     

AN ELECTRON MICROSCOPE STUDY OF MINERAL GROUP OF FRANCKEITE

Franckeite and cylindrite of franckite mineral group were examined in the transmission electron microscope. Selected-area electron diffraction indicated that in the structure exists a long period, belonging to an incommensurate modulation period. The incommensurate modulation in this kind of minerals results from sine undular structure sheets. The excellent correspondence between high resolution simulated computer image and observed image was obtained on the basis of the structure of franckeite and cylindrite which was put forward in this paper. First, the fact that in the structures of franckeite and cylindrite exist two kinds of structure sheets whose lattices are different has been proved by experiment, i. e. false tetragonal symmetrical galena structure sheets(t sheets)and false hexagonal SnS_2 sheets(h sheets). The two kinds of sheets are packed in order of htht…     

THE REFINEMENT OF CRYSTAL STRUCTURE OF BALIPHOLITE

Balipholite is a new mineral discovered in China. Its space group is C cca with the lattice parameters a=13.587(6), b=20.164(10), c=5.144(1). The structure was refined to an R value of 0.047 for 949 independent reflections with (|F_0|>3σ|F_0|). Balipholite has the simailar structure as that of the carpholite group but with large cations Ba occupying the caves of the structure. It is very interesting to point out that the additional anions F and OH occupy different crystallographic positions. Formula of balipolite can he written a BaMg_2LiAl_3(Si_2O_6)_2(OH)_4F_4.     

青河石(Qingheiite)的晶体结构

本文根据帕特逊法及富利叶合成测定了青河石的晶体结构,结构参数经最小二乘法修正后R=0.055,结构分析表明,青河石为wyllieite族中其M(2a)位置为Mg端员,M(1)位置为Mn端员的新矿物,晶体化学式为:Na_2NaMnMn_2Mg_2(Al,Fe)_2(PO_4)_6。     

安康矿一维无公度调制结构的电子衍射研究

用电子衍射方法研究了我国新发现的矿物安康矿(Ba_0.827(Ti_5.827V_2.294Cr_0.053)O₁₆)的一维无公度调制结构。确定了其平均结构属四方晶系,平均结构的晶胞参数为a=10.2?,c=2.96?。沿c方向的调制波长为λ=2.30c。详细分析了安康矿电子衍射花样的特征,讨论了安康矿无公度调制结构的可能机制,提出一个空位-位移型调制结构的模型,并讨论了因位移函数初始位相各处不一而引起的 关键词：     

纤钡锂石晶体结构的精测

纤钡锂石是一种在中国发现的新矿物,晶胞参数为α=13.587(6),b=20.164(10),c=5.144(1),空间群C cca。利用949个独立的衍射点(|F_0|>3σ|F_0|)对该结构进行修正,R=0.047。纤钡锂石的结构与纤锰柱石族相似,但大阳离子Ba占据了结构中的空洞位置。有趣的是该结构中附加阴离子F和OH占有不同的结晶学位置,因此,纤钡锂石的晶体化学式可写作BaMg_2LiAl_3(Si_2O_6)_2(OH)_4F_4。     

稀土氮杂大环配合物的研究(Ⅰ)——Na[Er(DOTA)·H_2O]·3H_2O的合成与晶体结构

合成了1,4,7,10-四氮杂-环十二烷-1,4,7,10-四乙酸(H_4DOTA)配体,在水溶液中培养了Na[Ln(DOTA)·H_2O]·3H_2O(Ln=Er,Yb)配合物单晶,测定了其热谱和红外光谱,用X射线衍射方法测定了Na[Er(DOTA)·H_2O]·3H_2O的晶体结构,属正交晶系,空间群P2_12_12_1,Z=4,晶胞参数:α=1.5795(8)nm,b=1.5777(8)nm,c=0.9142(5)nm,V=2.278(3)nm~3,配合单元中铒为九配位,其配位多面体为单冠四方反棱柱体。     

辉锑钖铅矿族矿物的电子显微镜研究

用透射电子显微镜法研究了辉锑锡铅矿族矿物中的辉锑锡铅矿和圆柱锡矿,表明其结构中具有的长周期属非公度调制周期。调制起因于结构层的正弦波状起伏。通过对所提出的结构模型计算得到的高分辨模拟象与观察象之间具有很好的匹配关系,从而在实验上首次证明了辉锑锡铅矿和圆柱锡矿结构中具有两种不同格子的结构层:假四方对称的方铅矿结构层(t层)和假六方对称的二硫锡矿结构层(h层),这两种层按htht……方式有序堆垛。     

CRYSTAL STRUCTURE OF A NEW PHOSPHATIC MINERAL——QINGHEIITE

The Qingheiite is a new mineral in the phosphate Wyllieite family. Space group P_(z1)/n, a=11.856, b=12.411, c=6.421, β=114.45°.The correct structure model has been obtained by using the Patterson method and Fourier synthesis. After the Structure parameter refinement, the R-factor reduced to 0.055. The structure analysis indicates that it is a new mineral in Wyllieite family which is Mg-end member in the M(2a) and Mn~(2 )-end member in the M(1). The crystallochemical formula is Na_2NaMn_2Mg_2 (Al, Fe)_2(PO_4)_6.     

稀土胺羧酸配合物的研究——Ⅰ.{[MnGd(DTPA)(H_2O)_5]_2·H_2O}_n配合物的合成和晶体结构

在水溶液中合成了二乙三胺五乙酸锰钆铒和钇的棱状晶体,元素分析结果表明可用{MnLn(DTPA)}_2·11H_2O表示(Ln为Gd,Er,Y;DTPA为二乙三胺五乙酸根).用X射线衍射方法测定了{MnGd(DTPA)}2·11H_2O的单晶结构,其结构式为{[MnGd(DTPA)(H_2O)_σ]_2·H_2O}n,属三斜晶系,空间群为PI,每一晶胞中有1个配合单元,形成一维链式配合物.晶胞参数如下:a=1.5896(3),b=0.8897(1),c=0.8146(1)nm;a=77.04(1),β=74.83(1),γ=88.21(1);Z=1:V=1.1191nm~3.配合物单元中钆为9配位,其配位多面体为三冠三角棱柱体;锰为6配位,形成八面体.