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1.
The salt triethylentetraammonium bis monohydrogen-monophosphate dihydrate is orthorhombic Pbca with unit cell dimensions a = 8.963(2), b = 10.326(2), c = 17.381(4)Å; Z = 4; Dm = 1.540 g cm–3; D x = 1.562 g cm–3. The examination of the structure shows a layer arrangement parallel to the axis: planes of [HPO4]2– tetrahedra alternate with planes of [(NH3(CH2)2NH2CH2)2]4+. The [HPO4]2– tetrahedra are connected through O(W)s--H···O hydrogen bonds, so that infinite chains of the composition [HPO4(H2O)]n 2n– are formed in the structure parallel to the axis. The structure of this compound is built from [HPO4]2– anions, [(NH3(CH2)2NH2CH2)2]4+ cations and zeolitic water molecules connected by hydrogen bonds.  相似文献   

2.
The salt triethylentetraammonium bis monohydrogenmonophosphate dihydrate is monoclinic with the following unit cell dimensions: a = 8.462(1), b = 10.500(1), c = 9.520 Å, = 99.297(1)°, space group P21/n with Z = 2. The structure was solved by the Patterson method and refined to final R value of 0.043 for 1590 independent reflections. The structure consists of infinite parallel two-dimensional [ 01] planes built of mutually connected ions and water molecules by strong O—H···O and N—H···O hydrogen bonding.  相似文献   

3.
The molecular structure of trans-W2(CO)6(PPh2H)2(2-PPh2)2 was determined by X-ray diffraction analysis. The two tungsten centers, bridged by two diphenylphosphido ligands, are separated by 3.0667(6) Å with W–P–W angles of 77.10(5) and 77.08(5). Average tungsten–phosphorus bond distances are 2.461(17) and 2.4576(21) Å for bridging and terminal phosphorus groups, respectively, with a range of 0.037 Å for the former and 0.001 Å for the latter. The complex crystallizes in the monoclinic space group P21/c with a = 19.282(4) Å, b = 12.158(2) Å, c = 21.294(9) Å, = 92.821(4), and Z = 4.  相似文献   

4.
The crystal structure of UO2Cl2(OH2)(MeCN)2·2MeCN has been determined at 123 K. The crystal is orthorhombic, space group Pnma, witha=14.891(8),b=6.733(6),c=15.931(9) Å, andD calc=2.18 g cm–3 forZ=4. The finalR value for 951 unique observed [F 05(F 0)] reflections is 0.064. The U atom is seven-coordinate, pentagonal bipyramidal. The two axial positions are occupied by the uranyl oxygen atoms. Within the equatorial plane lie two acetonitrile groups, two chlorine atoms and a water molecule, the latter positioned between the two chlorine atoms. All of the atoms except the uranyl oxygen atoms lie in crystallographic mirror planes. The water molecule is hydrogen bonded to the two uncoordinated solvent molecules. Several close contacts between the solvent methyl groups and chlorine atoms suggest weak C-H acidic interactions of the type C-HCl.  相似文献   

5.
本文研究了SiO2涂层对BaSi2O2N2∶ Eu2蓝绿色荧光粉发光性能和热性能的影响.采用溶胶-凝胶法制备了SiO2包覆的BaSi2O2N2∶Eu2+蓝绿色荧光粉.实验结果表明,最佳镀膜量为6wt;,当镀膜量大于此值时,荧光粉亮度迅速降低.涂覆SiO2后,在150℃下BaSi2O2 N2∶Eu2荧光粉的热猝灭性能提高了2.4;,在500℃热降解后荧光粉的发光性能提高了15;.SiO2涂层显著提高了BaSi2O2N2∶Eu2+荧光粉的热稳定性.SiO2涂层的作用机理是在荧光粉表面和氧化气氛之间形成阻挡层,保护Eu2的发光中心在热加热过程中不被氧化.  相似文献   

6.
7.
The title compound exists as a 1D coordination polymer consisting of succinate anions, manganese cations and 2,2-bipyridyl molecules. Twelve water molecules are present in the unit cell and are part of a hydrogen bonding system. Some of these waters are binding to manganese cations while others are only participating in hydrogen bonding. The structure has a monoclinic space group P21/c with a = 8.2750(3) Å, b = 11.5104(3) Å and c = 16.9113(6) Å, = 95.2727(16); V = 1603.96(9) Å3 and Z = 4.  相似文献   

8.
Abstract The synthesis of the PPN (PPN=Ph3P=N=PPh3) salt of di-μ-iodo-dichlorocuprate (I) anion [Cu2I2Cl2]2− is described and the crystal and molecular structures of this compound are reported. It was found that the compound has the formula [PPN]2[Cu2I2Cl2]0.7[Cu2I4]0.3 (3). Compound 3 crystallizes in an orthorhombic crystal system, space group Pbca, with a = 19.654(3), b = 16.130(2), c = 20.108(3) ?, V = 6374.3(16) ?3 and Z = 4. The crystal contains 70% [Cu2I2Cl2]2− anions and 30% [Cu2I4]2− anions. This was also confirmed by MSES spectroscopy. The anion [Cu2I2Cl2]2− is planar and the Cu atoms have a trigonal planar configuration. Graphical abstract Synthesis and Crystal Structure of the Salt [PPN + ] 2 [Cu 2 I 2 Cl 2 ] 2− Andrey A. Yakovenko, Tatiana V. Timofeeva and Mikhail Yu. Antipin The title compound was synthesized and structurally investigated. The crystal contains 70% [Cu2I2Cl2]2− anions and 30% [Cu2I4]2− anions. This was confirmed by MS ES spectroscopy.   相似文献   

9.
王超  黄春娥  陆小荣 《人工晶体学报》2014,43(11):3017-3021
针对铁红分相釉的配方特点,采用L8(4 ×24)正交实验研究了钠长石、牛骨灰、滑石、方解石、石英加入量对R2O-RO-SiO2-Al2O3-Fe2O3-P2O5系统分相釉釉面效果的影响,采用扫描电子显微镜(SEM)和能谱分析(EDS)对釉层的微观结构进行了表征.研究发现:牛骨灰对釉面是否出现“柿红”效果影响最显著,而方解石影响最不明显.Si/P摩尔比对铁红色釉面的产生起关键作用,当Si/P摩尔比小于2O,出现铁红釉面效果的概率极高.随着滑石加入量从9份变化到18份,出现铁红色釉面的趋势反而降低.经SEM和EDS分析发现,“柿红色”、“酒红色”釉面效果的产生很大程度上是由于釉层液液分相促进Fe2O3富集或偏析造成,且特别容易在高钠、低镁、低铝处聚集,最终连成雪花状结晶.  相似文献   

10.
[WBr2(Co)(PPh2Cy)2(2-MeC2Me)]·CH2Cl2 (Cy = cyclohexyl) crystallizes in the monoclinic space group, P21/n, with a = 10.606(12), b = 23.11(3), c = 18.19(2) Å, = 106.070(10) Dcalc = 1.610g cm–3 for Z = 4. The tungsten coordination geometry can best be considered as a distorted octahedron, with the but-2-yne ligand occupying one coordination site, which has a trans-Br(2) group. The equatorial plane is made up of trans-PPh2Cy groups, with the bromo and carbonyl ligands occupying the other two sites.  相似文献   

11.
The crystalline products [Me2Al–N(CH2CH2)2–C–(OCH2)2]2 (I) and [Me2Ga–N(Si(H)Me2)2]2 (II) were prepared from reactions of trimethylaluminum and trimethylgallium with 1,4-dioxa-8-azaspiro[4.5]-decane and 1,1,3,3-tetramethyldisilazane, respectively, in toluene. The organoaluminum dimer crystallizes in the monoclinic space groupP21/c with unit cell parametersa=8.970(2) ,b=9.683(2) ,c=12.833(3) , =103.18(2)°,V=1085.3(3) 3, andD calcd=1.22 g cm–3 forZ=2. Least-squares refinement based on 935 observed reflectionsI>3(I) in the range 3.5°<2<45.0° led to a finalR factor of 0.033 (R w =0.041). The dimeric organosilazagallium crystallizes in the triclinic space group with unit cell parametersa=7.636(2) ,b=9.168(2) ,c=9.466(3), =72.81(2)°, =87.94(2)°, =69.90(2)°,V=593.0(3) 3, andD calcd=1.30 g cm–3 forZ=1. Least-squares refinement based on 1661 observed reflectionsI>3(I) in the range 3.5°<2<48.0° led to a finalR factor of 0.055 (R w =0.070). Both compoundsI andII reside about a crystallographic center of symmetry and contain a planar M2N2 (M=Al forI, Ga forII) four-membered ring withI having an Al...Al contact of 2.801 .  相似文献   

12.
本文研究了SiO_2涂层对BaSi_2O_2N_2∶Eu~(2+)蓝绿色荧光粉发光性能和热性能的影响。采用溶胶-凝胶法制备了SiO_2包覆的BaSi_2O_2N_2∶Eu~(2+)蓝绿色荧光粉。实验结果表明,最佳镀膜量为6wt%,当镀膜量大于此值时,荧光粉亮度迅速降低。涂覆SiO_2后,在150℃下BaSi_2O_2N_2∶Eu~(2+)荧光粉的热猝灭性能提高了2. 4%,在500℃热降解后荧光粉的发光性能提高了15%。SiO_2涂层显著提高了BaSi_2O_2N_2∶Eu~(2+)荧光粉的热稳定性。SiO_2涂层的作用机理是在荧光粉表面和氧化气氛之间形成阻挡层,保护Eu~(2+)的发光中心在热加热过程中不被氧化。  相似文献   

13.
通过化学腐蚀和偏光显微镜,对KBe2BO3F2(KBBF)和RbBe2BO3F2 (RBBF)晶体中存在的一种条状孪晶缺陷进行了研究,观察了孪晶习性,探讨了其孪晶律,并结合晶体生长情况对该孪晶的形成原因进行了分析.  相似文献   

14.
K2Al2B2O7(KABO)晶体是近年发现的一种有应用前景的深紫外非线性光学晶体,也是目前唯一一种可以生长出大尺寸单晶的BO3基团非线性光学晶体.KABO有可能用于固态激光器的266nm及193nm高功率输出.本文对该晶体的物理化学性质及热学性质进行了研究,KABO晶体不潮解,不溶于水、酒精等溶剂,可溶于盐酸,硝酸和磷酸等强酸;测得莫氏硬度为5.5~6.5,用浮力法测得其密度为2.47g/cm3;用差热分析(DTA)方法测量其熔点为1109.7℃.用热重分析(TGA)方法结合分解产物的粉末X射线衍射(XRD)分析,确定KABO在900℃以上开始分解,分解产物主要为KAl11O17和K2Al24O37;用热机械分析仪测量了其热膨胀系数,沿物理学轴X、Y、Z方向分别为8.4×10-6/K、7.7×10-6/K、1.65×10-5/K.在室温至300℃温度范围内测量了KABO晶体的比热变化,比热随温度的升高线性增大.在47.6℃和294.6℃时比热分别为1.0084J/g℃与1.39J/g℃.  相似文献   

15.
《Journal of Non》1997,217(1):99-105
27Al and 29Si MAS NMR studies were performed on roller-quenched SiO2Al2O3-glasses with Al2O3 contents ranging from 10 to 60 mol% and on SiO2Al2O3Na2O glasses containing 10 mol% Al2O3 and 2.5 to 10 mol% Na2O. Pure aluminium silicate glasses show NMR peaks at 0, 30 and 60 ppm. The frequency distribution of the different Al-sites is not affected by the glass composition. In glasses of the system SiO2Al2O3Na2O the 30 ppm peak decreases to zero as the Na2O content increases. The 30 ppm peak is assigned to distorted triclustered AlO-tetrahedra, rather than to fivefold coordinated Al. Triclustering of tetrahedra may provide for charge neutrality in glasses with molar excess of Al2O3 over Na2O. As charge balance is increasingly achieved by addition of alkali ions, the tendency of tetrahedral triclustering is reduced, reflected by the disappearance of the 30 ppm peak in glasses containing ≥ 7.5 mol% Na2O.  相似文献   

16.
The structure of ZnI2 · 2CO(NH2)2 is determined by single-crystal X-ray diffraction. The crystals are monoclinic, a = 12.694(3) Å, b = 6.886(2) Å, c = 13.161(3) Å, β = 110.58(2)°, Z = 4, space group P21/a, and R = 0.0337 for 2481 reflections. Similar to the chloride analogue, the structure consists of discrete molecules with tetrahedrally coordinated Zn atoms. The bond lengths and angles are as follows: Zn-I, 2.5749(8) and 2.5473(8) Å; Zn-O, 1.954(3) and 1.985(4) Å; IZnI, 113.74(3)°; OZnO, 100.5(2)°; and IZnO, 108.5°–113.1(1)°. The crystal structure agrees with the IR and electronic absorption spectra of the crystals.  相似文献   

17.
通过引入B2O3以降低烧成温度,利用赤泥中的Fe2O3为着色剂,在1150℃左右低温烧成制备了CaO-MgO-Al2O3-Fe2O3-B2O3-SiO2系微晶釉.赤泥的加入量为20;左右时,釉面具有良好的装饰效果和显微硬度.利用XRD、SEM研究了釉的物相及显微组织.结果表明,釉中析出的微晶是普通辉石,微晶的含量随MgO及CaO的含量增加而增加,而提高Al2O3含量则抑制微晶的析出.  相似文献   

18.
The ethylenediammonium pentachlorobismuthate(III) dihydrate salt is monoclinic with the following unit cell dimensions: a = 10.902(8)Å, b = 7.926(6)Å, c = 15.199(6)Å, = 96.40(1)°, space group P21/n with Z = 4. The structure shows a layer arrangement parallel to the axis: planes of the [Bi2Cl10]4– bioctahedra alternate with planes of [NH3(CH2)2NH3]2+ dications. The [Bi2Cl10]4– bioctahedra are connected through O(W)–H··· Cl hydrogen bonds, so that infinite unidimensional chains of composition [Bi2Cl10(H2O)2] n 4n– are formed in the structure parallel to the axis. These chains are themselves interconnected by means of the N–H···Cl bonds originating from the [NH3(CH2)2NH3]2+ entities, forming a three-dimensional network.  相似文献   

19.
配合物[Cu2(C6H2Cl2OC=N-C3H6COO)2(H2O)2]·3H2O合成与晶体结构   总被引:1,自引:0,他引:1  
本文以苏氨酸,3,5-二溴水杨醛以及醋酸铜为原料合成了新型配合物[Cu2(C6H2Cl2OC=N-C3H6COO)2(H2O)2]·3H2O,并对其晶体结构经元素分析,红外光谱及X射线单晶衍射表征.结果表明:该晶体属单斜晶体结构,晶胞参数分别为:a=0.6985(2) nm, b=1.0789(2) nm, c=1.9639(3) nm, β=92.182(3) °, Mr=797.34, V=1.4789(6) nm3 , Z=2, Dc=1.790 g/cm3, μ(MoKa) =1.867 mm-1, F(000)=808, R=0.0321, wR= 0.0566.Cu(II)与一个N原子,两个O原子以及一个水分子构成三齿链状席夫碱.不对称单元结构包含两个配合物分子及三个由氢键链接的水分子.  相似文献   

20.
Potassium and ammonium dimeric (citrato)dioxovanadium(V) hydrate K2[VO2(H2cit)]2·4H2O1 and (NH4)2[VO2(H2cit)]2·2H2O2 (H4cit=citric acid) have been prepared and characterized by X-ray structure analyses. Vanadate1 crystallizes in the monoclinic space groupP21/n (No. 14) with unit cell parameters:a=9.304(2),b=11.756(2),c=11.911(2)Å, =111.72(3)°, andD c=1.911 g/cm3,Z=2; Vanadate2 also crystallizes in the monoclinic space groupP21/n with unit cell parameters:a=9.719(2),b=11.111(3),c=11.294(2)Å, =109.03(2)°, andD c=1.781 g/cm3,Z=2. Each dimer contains a centro-symmetric planar four-member V2O2 ring with two exocyclic citrate entities coordinated by the oxygen atoms of the hydroxy-and -carboxylate ligands, while the other two -carboxylate groups remain uncomplexed. Principal dimensions of the V–O bonds are 1.986(4)av (hydroxy) and 1.980(3)Å(-carboxyl) for vanadate1, 1.988(2)av (hydroxy) and 1.974(3)Å(-carboxyl) for vanadate2.  相似文献   

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