Short H· · ·H distances in norbornene derivatives

A short H···H intramolecular interaction was reported previously for an anhydride of syn-sesquinorbornene. The synthesis and structure of a such an anhydride with an additional five-membered dithiole ring has been investigated. While hydrogen atom positions are not accurately located, the 1.62 Å separation indicates this molecule is a candidate for the shortest H···H interaction. Two cycloadducts of norbornadiene, which literature suggests might exhibit additional short interactions, are reported also; however, the isomers with minimal intramolecular interactions are the isolated products. C₂₂H₂₀O₃S₂, 3, crystallizes in P with a = 10.881(4), b = 13.712(8), C = 6.548(8) Å, = 101.32(6), = 107.49(5), = 90.49(4)°, D _calc = 1.445 g cm^–3, and Z = 2, C₂₁H₂₀O₄Cl₈, 5, in P2₁/n with a = 8.168(2), b = 13.488(4), c = 23.500(6) Å, = 94.72(2)°, D _calc = 1.597 g cm^–3, and Z = 4, C₂₁H₂₈O₄, 6, in P> with a = 12.667(2), b = 12.792(2), c = 12.540(2) Å, = 113.51(1), = 98.18(1), = 74.39(1)°, D _calc = 1.276 g cm^–3, and Z = 4.     

Crystal structures of acid ethylenediaminetetraacetates [Cd(H2 Edta)(H2O)] · 2H2O and [Mn(H2O)4][Mn(HEdta)(H2O)]2 · 4H2O

The crystal structures of [Cd(H₂ Edta)(H₂O)] · 2H₂O (I) and [Mn(H₂O)₄][Mn(HEdta)(H₂O)]₂ · 4H₂O (II) are studied by X-ray diffraction [R ₁ = 0.0209 (0.0272), wR ₂ = 0.0571 (0.0730) for 2551 (4025) reflections with I > 2σ(I) in I (II), respectively]. Structure I contains mononuclear [Cd(H₂ Edta)(H₂O)] complexes with the C ₂ symmetry, and structure II contains centrosymmetric trinuclear [Mn(H₂O)₄][Mn(HEdta)(H₂O)]₂ complexes. In I and II, the protonated ligands are hexadentate (2N + 4O), and the water molecule increases the coordination number of the metal atom to seven. The acid protons participate in short intermolecular hydrogen bonds, which are symmetric in II and asymmetric in I.     

Crystal structure of aminoguanidinium hexahydro-closo-hexaborate dihydrate, (CN4H7)2B6H6 · 2H2O

The (HAgu)₂B₆H₆ · 2H₂O compound was synthesized and its crystal structure was determined [R = 0.0385 for 2018 reflections with I > 2σ(I)]. The structure consists of HAgu ⁺ cations, centrosymmetric B₆H ₆ ^2? anions, and water molecules. The anions have an almost regular octahedral structure. The bond lengths and angles lie within the following narrow ranges: B-B, 1.715–1.726(2) Å; B-H, 1.08–1.14(2) Å; B-B-B, 59.72°–60.29(9)° and 89.63°–90.20(11)°; and B-B-H, 133.2°–137.0(9)°. The HAgu ⁺ cations and water molecules are involved in the O-H?O, N-H?O, and N-N?N hydrogen bonds and participate in numerous (N, O)-H?H-B specific interactions with the B₆H ₆ ^2? anions, which results in splitting and high-frequency shift of the band of B-H stretching vibrations in the IR spectrum.     

Direct-PECVD a-SiOx:H/a-SiNx:H 叠层系统对多晶硅电池的钝化研究

本文中应用全部PECVD工艺沉积a-SiOx:H、a-SiNx:H,和a-SiOx:H/a-SiNx:H叠层系统,比较了不同钝化膜对多晶硅太阳能电池发射极和背面钝化效果,应用FGA、RTP等热处理方法对钝化膜进行处理,重点讨论了FGA(Forming gas annealing)温度和时间的长短对钝化的影响.结果表明:低温FGA对只有单面钝化膜的硅片钝化效果不明显,而在800 ℃下FGA有明显作用,而且钝化效果随着时间的增加呈现出先增大后减小然后再增大的现象;退火后降温环境中是否有H和降温时间对钝化效果有很大的影响,但是对于双面膜无论FGA温度高低对钝化都有帮助,文中对上述现象做了合理的解释.最后利用双面叠层钝化膜经过FGA处理后得到的多晶硅片的少子寿命达到14.2 μs,比镀膜之前的3.0 μs提高了11.2 μs,使多晶硅太阳能电池暗电压 Voc达到630 mV.     

4H碳化硅单晶中的位错

4H碳化硅(4H-SiC)单晶具有禁带宽度大、载流子迁移率高、热导率高和稳定性良好等优异特性,在高功率电力电子、射频/微波电子和量子信息等领域具有广阔的应用前景。经过多年的发展,6英寸(1英寸=2.54 cm)4H-SiC单晶衬底和同质外延薄膜已得到了产业化应用。然而,4H-SiC单晶中的总位错密度仍高达10³~10⁴ cm^-2,阻碍了4H-SiC单晶潜力的充分发挥。本文介绍了4H-SiC单晶中位错的主要类型,重点讲述4H-SiC单晶生长、衬底晶圆加工以及同质外延过程中位错的产生、转变和湮灭机理,并概述4H-SiC单晶中位错的表征方法,最后讲述了位错对4H-SiC单晶衬底和外延薄膜的性质,以及4H-SiC基功率器件性质的影响。     

从P-a-SiC:H到P-μc-Si:H过程中材料特性的变化

采用RF-PECVD方法,在P-a-SiC:H薄膜沉积技术基础上,通过逐步减小碳、硼的掺杂浓度,增大氢稀释率,使材料从非晶态向微晶态转变,在获得本征微晶材料之后,再逐步增大硼掺杂浓度,得到P型微晶硅薄膜材料(暗电导率为5.22×10-3S/cm,光学带隙大于2.0eV).在这个过程中可以明显观察到碳、硼抑制材料晶化的作用.     

配合物[Cu2(C6H2Cl2OC=N-C3H6COO)2(H2O)2]·3H2O合成与晶体结构

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.     

Crystal structure of N-benzylmethylammonium dihydrogen-monophosphate monohydrate, [C6H5CH2NH2CH3]H2PO4·H2O

The salt N-benzylmethylammonium dihydrogenmonophosphate monohydrate is monoclinic with the following unit cell dimensions: a = 6.356(1)Å, b = 8.385(7)Å, c = 11.472(5)Å, = 104.32(1)°, space group P2₁ with Z = 2. The structure consists of infinite parallel two-dimensional [110] planes built of mutually connected ions and water molecules by strong O–H···O and N–H···O hydrogen bonding. There are no contacts other than normal van der Waals interactions between the layers.     

Crystallographic analysis of Royline monohydrate [C25H41NO7 · H2O]

The crystal and molecular structures of the alkaloid Royline {(1α,6β,14α, 16β)-20-ethyl-4-hydroxymethyl)-1,6,14,16-tetramethoxyaconitane-7,8-diol} with a water molecule has been determined by X-ray diffraction analysis. The compound crystallizes in the space group P2₁ with the unit cell parameters a = 10.985(1) Å, b = 7.898(1) Å, c = 14.956(1) Å, β = 102.96(1)°, V = 1264.52 ų, Z = 2, λMoK _α = 0.71073 Å, and R = 0.033 for 2067 observed reflections. Rings A, B, and C adopt a chair conformation, ring D is a half-boat, ring E is a half-chair, and ring F is in an envelope conformation with C(14) at the flap. Molecules are linked together in the crystal by hydrogen bonds.     

[Co(H2O)6](C18H15O4SO3)2·4H2O的合成和晶体结构

以芒柄花素为先导化合物,合成了水溶性的[Co(H2O)6](C18H15O4SO3)2·4H2O,并采用IR, 1H NMR, TG-DTA, XRD和单晶X射线衍射法对其结构进行了表征.单晶X射线衍射结果表明:[Co(H2O)6]2+、C18H15O4SO 3和H2O之间存在多种氢键,形成晶体结构中的亲水区.异黄酮骨架间反平行排列,面对面和边对面芳香堆积作用同时存在于其中,构成晶体结构中的疏水区.磺酸根是连接亲水区和疏水区的桥梁.氢键、芳香堆积作用以及阴阳离子之间的静电引力共同将标题化合物组装成具有三维网络结构的超分子.     

Synthesis and crystal structure of [Ni(H2O)6](C19H17O9S)2·2H2O

A water soluble flavonoid sulfate, [Ni(H₂O)₆](C₁₉H₁₇O₉S)₂·2H₂O was synthesized and its structure was determined by single-crystal X-ray diffraction analysis. The crystal of it belongs to triclinic crystal system, space group P–1. The results show that the title compound consists of [Ni(H₂O)₆]²⁺, C₁₉H₁₇O₆SO₃ ⁻ and H₂O. Ni(II) is located on the symmetry center and octahedrally coordinated by six water molecules. A variety of hydrogen bonds among [Ni(H₂O)₆]²⁺, C₁₉H₁₇O₆SO₃ ⁻ and the lattice water molecules build a hydrophilic region. Aromatic π–π stacking interactions assemble isoflavone skeletons into a column and the columns form a hydrophobic region of the title compound. The sulfo-groups bridge the hydrophilic regions and the hydrophobic regions as well as the inorganic components and organic components. Hydrogen bonds, stacking interactions and the electrostatic interactions between cation [Ni(H₂O)₆]²⁺ and anion sulfonate C₁₉H₁₇O₆SO₃ ⁻ lead the moieties to a three-dimensional structure.     

Deposition of phosphorus doped a-Si:H and μc-Si:H using a novel linear RF source

A roll-to-roll PECVD system for thin film silicon solar cells on steel foil has been developed by ECN in collaboration with Roth and Rau AG. It combines MW–PECVD for fast deposition of intrinsic Si and novel linear RF sources, which apply very mild deposition conditions, for the growth of doped Si layers. The RF and MW sources can be easily scaled up to deposition widths of up to 150 cm. Here, we report on n-type doping, achieved by RF–PECVD from a H₂/SiH₄/PH₃ mixture in the reaction chamber. The best n-type a-Si:H layers showed E_act = 0.27 eV and σ_d = 2.7 × 10^?3 S/cm. Also thin layers down to 20 nm were of device quality and were deposited at a rate of 0.4 Å/s. Furthermore, n-type μc-Si:H layers with thicknesses of 150 nm, with E_act = 0.034 eV and σ_d = 2 S/cm were grown. Good quality n-type μc-Si:H layers can be made for layer thicknesses down to 50 nm at a rate of 0.15 Å/s. To conclude, the novel RF source is well-suited for the growth of n-doped a-Si:H and μc-Si:H layers for roll-to-roll solar cell production.     

Synthesis and structure determination of a new layered zincophosphate: [H2N2C6H16]0.5[Zn2(PO4)(HPO4)(H2O)]·H2O

The synthesis and crystal structure of a new microporous zincophosphate are described. [H₂N₂C₆H₁₆]_0.5[Zn₂(PO₄)(HPO₄)(H₂O)]·H₂O crystallizes in the triclinic space group P1¯ with a = 8.822(4), b = 9.236(4), c = 8.451(3) Å, = 67.19(3), = 91.32(3), = 111.10(3)°, V = 586.7(4) ų and Z = 2. This new material consists of infinite two-dimensional anionic layers alternated with planes containing organic diprotonated templates, N, N, N, N-tetramethylethylenediamine [H₂N₂C₆H₁₆]²⁺ molecules. The framework structure is built up of ZnO₄, ZnO₃OH₂, PO₄, and PO₃OH tetrahedra, linked through oxygen vertices. The presence of terminal OH₂ and OH groups, leads to an open structure containing four- and eight-rings. The organic molecules are interconnected to the framework through hydrogen bonds.     

H2流量对直流磁控溅射制备a-Si∶H薄膜微观结构及光学性能的影响

采用直流磁控溅射法在不同H2流量的条件下制备了a-Si∶H薄膜,研究了H2流量对薄膜微观结构以及光学性能的影响.结果表明:随H2流量的增加,a-Si∶H薄膜的沉积速率有所下降,但其原子排列的有序度上升,并出现了细小的纳米晶粒,使得薄膜的无序结构得到了一定改善.同时,薄膜的光学性能也表现出明显变化,其中透过率持续上升,而光学带隙则呈现出先增大后减小的趋势.最终得到制备a-Si∶H薄膜的最优H2流量为15 sccm.     

Structure of progesterone hydroquinone monohydrate (1∶1∶1), C21H30O2·C6H6O2·H2O

The crystal structure of progesterone hydroquinone monohydrate was determined by means of X-ray diffraction methods:M _r=442.6, orthorhombic,P2₁2₁2₁,a=14.680(2),b=22.725(3),c=7.334(1) Å,V _a=2446.6(6) ų,Z=4,D _x=1.190 M gm^–3, MoK radiation ,(MoK)=0.75 cm^–1,F(000)=948. The structure was solved usingMultan;R=0.059,R _w=0.059 for 2736 reflections. This progesterone molecule has the most flattenedA ring, relative to the rest of the skeleton, of all progesterone molecules studied so far. Steroid, hydroquinone, and water molecules form, by means of hydrogen bonds, two parallel chains connected with each other by hydrogen bonds.The authors thank Dr. A. Szyczewski for supplying crystals. This research was supported by the project RP.II.10 from the Polish Ministry of National Education and by PHS Grant No. DK26546.     

C−H...π(Ar)...H−C host-guest interactions in a novel air-stable cyanoborate clathrate

The host compound forms a coordinato-clathrate in a coordination assisted host lattice. The host lattice is provided by hydrogen bonding between the nitrogen atom of the cyano group and two hydrogen atoms from the phosphonium methyl group. Guest molecules ofp-xylene occupy constricted channels in the lattice. The twop-xylene molecules participate in C–H...(Ar)...H–C interactions. Results from searches of the Cambridge Structural Database for other C–H...(Ar)...H–C and C–H...(Ar) interactions are presented.     

Crystal and molecular structure of 7-hydroxyflavone monohydrate, C14H10O3·H2O

The X-ray crystal structure of 7-hydroxyflavone monohydrate, C₁₄H₁₀O₃ · H₂O, is determined. The compound crystallizes in the monoclinic space group, P2₁/n with a = 3.801(3), b = 19.665(4), c = 16. 039(6), = 93.69(3)°, and = 0.68 mm^–1 for Z = 4. The phenyl ring of the flavone moiety is rotated 18.6(1)° out of the penzopyran plane, which is a typical value for flavones. In the crystal lattice, there are wide channels which are lined mainly by C–H groups. The water molecules enclosed in these channels are severely disordered.     

BaBPO5和(H3O)Zn(H2O)2BP2O8·H2O的低温溶剂热合成及表征

以乙醇为溶剂,在低温条件下合成出了两种手性硼磷酸盐化合物BaBPO5(1)(T=120℃,t=5d)和(H3O)Zn(H2O)2BP2O8·H2O (2)(T=80℃,t=5d).XRD单晶衍射仪测定了化合物的结构,结果表明:(1)属三方晶系,P3221空间群,a=b=7.1162(3)(A),c=6.9979(6),(A)=3,该晶体含有一维线性链状阴离子结构;(2)属六方晶系,P6122空间群,a=b =9.513(2)(A),c=15.906(8),(A)=6.该晶体具有三维骨架结构.实验结果表明使用乙醇作溶剂可以极大降低硼磷酸盐的合成温度,进而有助于获得手性硼磷酸盐化合物,这为手性硼磷酸盐的合成提供了一种新思路.