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1.

Abstract  

A new compound having potential bioactivities 3,5-dichloro-6-morpholinopyridin-2-ol (1) was synthesized and characterized by single crystal X-diffraction. The crystal is monoclinic, space group P21/c with a = 10.3609 (6), b = 10.5711 (7), c = 10.3190 (5) ?, β = 108.9433 (15)°, V = 1068.99 (11) ?3, Z = 4, C9H10Cl2N2O2, D c  = 1.548 g/cm3, μ (MoKα) = 0.71075 ?, S = 1.01, F (000) = 512.00, R = 0.0397 and wR = 0.1364. In the unit cell, there are two independent molecules linked by intermolecular O–H···O (2.693(2) ?) hydrogen bonds forming onedimensional expanded structure.  相似文献   

2.
6-nitro-2-trichloromethyl-1,3-benzdioxin-4-one is monoclinic,P21/n;a=5.969(2),b=11.646(1),c=16.953(1) Å;=98.03(2)°;Z=4. The structure was solved by direct methods, from data collected at room temperature on an Enraf-Nonius CAD4 diffractometer, and refined by least squares to a finalR value of 0.030 using 1530 reflections.The heterocyclic ring is a distorted half-boat and is substituted equatorially by a trichloromethyl group. Dihedral angles are (a) 4.87(7)° between the mean plane of the aromatic ring and the plane containing the two carbon atoms common to both rings plus the two atoms bonded to these, and (b) 16.8(2)° between the carbonyl group and the aromatic ring. The conformation is discussed with reference to the two previously reported X-ray structures of 1,3-benzdioxin-4-ones and to two isocoumarins.  相似文献   

3.
6-Nitro-trichloromethy1-4-dichloromethylene-1,3-benzdioxin is monoclinic,C2/c,a=12.906(2) Å,b=19.957(2) Å,c=19.992(2) Å,=99.05(1)°,Z=8. The structure was solved by direct methods, from data collected at room temperature on an Enraf-Nonius CAD4 diffractometer, and refined by least squares to a finalR value of 0.032 using 1838 reflections.The compound exhibits a distorted envelope structure in the dioxin ring, and the trichloromethyl group is in the equatorial position. The angle between the planes each containing a group of three atoms from either end of the double bond of the:C(ring)=CCl2 moiety is 3.8(2)°: a short discussion of deformations found in other compounds which contain:C(ring)=CC12 in light atom structures is given. The benzene ring is slightly puckered and planarity has been retained about the carbon atoms which are common to both rings.  相似文献   

4.
在Rb2 CO3-Li2 CO3-Gd2 O3-H3 BO3体系中,用自发结晶的方法获得了一种钆硼酸盐Rb2 LiGdB2 O6(RLGBO)单晶,同时,用固相合成法获得了RLGBO粉末多晶.单晶结构解析表明,RLGBO属于正交晶系,Pbcm空间群,晶胞参数a=7.0259(3)?,b=9.6103(4)?,c=10.0562(4)?和z=4.热学性质表明,RLGBO在840℃下保持良好的热稳定性.在RLGBO中分别掺杂2;的Ce3+,80;的Eu3+和50;的Tb3+之后,其结构不会发生改变.在紫外光及近紫外光激发下,RLGBO:Ce3+,RLGBO:Eu3+和RLGBO:Tb3+可分别发射蓝光,红光和绿光.结果表明,RLGBO化合物可作为发光物质的基质材料.  相似文献   

5.
Abstract  Reported within is the crystal structure of 4,13-diaza-18-crown-6 and NaI (P21/c; a = 7.0732(5) ?, = 15.4058(10) ?, c = 9.9605(6) ?, b = 96.7950(10)°, V = 1077.75(12) ?3, Z = 2). The structure was obtained serendipitously from a crystallization attempt of these two components in the presence of indole. There are two non-equivalent sodium cations, one encapsulated within the diazacrown, and a second cation linking two adjacent diazacrowns and coordinating to both. The sodium cations are also linked through a water bridge. This leads to the formation of infinite 1–D chains in which iodide counterions occupy the space between the chains. This is the first reported example of an unsubstituted 4,13-diaza-18-crown-6 encapsulating Na+. The first structure of 4,13-diaza-18-crown-6 and NaI containing two symmetrically inequivalent Na+ ions, only one of which is encapsulated by the diazacrown, is reported. Index Abstract  The first structure of 4,13-diaza-18-crown-6 and NaI containing two symmetrically inequivalent Na+ ions, only one of which is encapsulated by the diazacrown, is reported
George W. GokelEmail:
  相似文献   

6.
Abstract  The title compound 2-(2,3,4-trimethoxy-6-methylbenzylideneamino)phenol (C17H19NO4, M r = 301.33) was synthesised and characterized by elemental analysis, IR spectra and single crystal X-ray diffraction. The crystal belongs to monoclinic, space group P21/c, with a = 10.4458(14), b = 8.3870(10), c = 17.780(2) ?, β = 91.102(2)°, V = 1557.4(3) ?3, Z = 4, D c = 1.285 g/cm3, λ = 0.71073 ?, μ(Mo ) = 0.092 mm−1, F(000) = 640. The final refinement gave R = 0.0452, wR(F 2) = 0.1065 for 2,743 observed reflections with I > 2σ(I). X-ray diffraction analysis reveals that the molecule adopts an E configuration at the C=N functional bond. The dihedral angle between the two phenyl rings is 38.3(3)°. The crystal structure is stabilized by C–H···O, O–H···O and O–H···N hydrogen bonds and π–π stacking interactions. Graphical Abstract  The title compound 2-(2,3,4-trimethoxy-6-methylbenzylideneamino)phenol (C17H19NO4, M r = 301.33) was synthesised and characterized by elemental analysis, IR spectra and single crystal X-ray diffraction. The crystal belongs to monoclinic, space group P21/c, with a = 10.4458(14), b = 8.387(1), c = 17.780(2) ?, β = 91.102(2)°, V = 1557.4(3) ?3, Z = 4, D c = 1.285 g/cm3, λ = 0.71073 ?, μ(Mo ) = 0.092 mm−1, F(000) = 640. The final refinement gave R = 0.0452, wR(F 2) = 0.1065 for 2,743 observed reflections with I > 2σ(I). X-ray diffraction analysis reveals that the molecule adopts an E configuration at the C=N functional bond. The dihedral angle between the two phenyl rings is 38.3(3)°. The crystal structure is stabilized by C–H···O and O–H···O hydrogen bonds and π–π stacking interactions.   相似文献   

7.
Single crystals of La2NaTaO6 were grown out of a reactive high-temperature hydroxide melt. The structure was determined by single crystal X-ray diffraction. La2NaTaO6 adopts the monoclinically distorted double perovskite structure type with general formula A2BB′O6, where tantalum atoms are located on the B′ site. La2NaTaO6 crystallizes in the monoclinic space group P21/n with a=5.6904(2) Å, b=5.9824(2) Å, c=8.1423(2) Å and β=90.8650(10)°? An optical bandgap of 4.5 eV was estimated from the UV–vis diffuse reflectance spectrum.  相似文献   

8.
Single crystals of tribarium gallate (Ba3Ga2O6) have been synthesized from a melt with composition 70 mol.% BaO and 30 mol.% Ga2O3 in the temperature range between 1200 °C and 1400 °C. The compound adopts space group Pa with a = 16.746(9) Å and Z = 24 formula units per unit cell. The refinement of the atomic parameters resulted in a residual of R1 = 0.040 (wR2 = 0.102) for 1157 observed reflections (I>2 σ (I)). Ba3Ga2O6 belongs to the group of cyclo‐gallates and is closely related to K4SrGe3O9. Main building element are isolated, highly puckered, twelve‐membered rings build by [GaO4]‐tetrahedra. Charge balance is achieved by incorporation of Ba ions in the voids between the rings. The coordination number of the alkaline earth atoms is six, eight and nine, respectively.  相似文献   

9.
采用基于密度泛函理论的平面波赝势方法,计算了不同压强下立方结构双钙钛矿氧化物Ba2YNbO6的弹性性质与电子结构.计算结果表明:平衡状态下Ba2YNbO6为延展性材料,且延展性随压强的增大而提高;弹性常数,弹性模量和泊松比均随压强的增大近线性增大;Ba2YNbO6为直接带隙半导体,平衡状态下带隙宽度为2.55 eV,且带隙值随压强的增大而减小;费米面附近的能带主要由O 2p,Nb 4d和Y 4d层的电子态密度确定,增大压强使态密度峰有偏离费米面的趋势,并且态密度展宽,峰发生劈裂.  相似文献   

10.
11.
12.
本文采用固相反应法探索了Aurivillius结构Bi2MoxW1-xO6体系的合成条件以及能够形成固溶体的成分范围,探索了Bi2MoxW1-xO6晶体的助熔剂法生长体系,并对晶体的结构、变温介电性质和电阻率进行了测定和分析。Bi2MoxW1-xO6体系中Mo的占比x可以在0~1的范围内连续变化,采用固相反应法可以在500~870 ℃范围内的不同温度合成纯的Bi2MoxW1-xO6铁电相。采用Li2B4O7-Bi2O3(摩尔比2∶1)作为助熔剂生长得到了厘米级Bi2WO6单畴晶体,厚度不小于2 mm,最大尺寸则达到了约40 mm。在n(Bi2O3)∶n(MoO3)∶n(WO3)∶n(Li2B4O7)=1∶1∶1∶1(摩尔比)体系中生长得到了厚度约1 mm的Bi2Mo0.15W0.85O6厘米量级单畴晶体,结构解析表明Bi2Mo0.15W0.85O6属于正交晶系,Aba2(No.41)空间群。变温介电性质测试表明,Bi2Mo0.15W0.85O6晶体的介电常数ε33由Bi2WO6晶体的70提高到了102,介电弛豫现象发生的温度由Bi2WO6晶体的430 ℃降到了330 ℃附近。变温电阻率测试表明,Bi2WO6与Bi2Mo0.15W0.85O6晶体的电阻率均随温度升高而降低,在100 ℃以下,Bi2WO6的电阻率高于Bi2Mo0.15W0.85O6晶体,且随温度升高,二者电阻率的差距在逐渐缩小。  相似文献   

13.
Chemical preparation, X-ray single-crystal, thermal behavior, and IR spectroscopy studies of a new dihydrogenmonophosphate associated to an organic cation, the 3-(ammoniummethyl)pyridine dihydrogenmonophosphate (denoted as AMPP) are described. The AMPP crystallizes in the monoclinic system with P21/c space group. The unit cell dimensions are a = 5.8465(2) Å, b = 19.9776(9) Å, c = 7.3103(3) Å, = 90.848(3)° with V = 853.74(4) Å3 and Z = 4. The structure has been solved using direct method and refined to a reliability R factor of 0.0393. The structure of AMPP includes three types of hydrogen bonds. The first one, O H O, links the H2PO4 groups to form infinite inorganic chains [H2PO4]n n–, parallel to the c axis. The two other types, O H N and N H O assemble inorganic chains so as to build up a three-dimensional arrangement.  相似文献   

14.
以葡萄糖(C6H12O6),分析纯硝酸铋(Bi(NO3)3·5H2O)和钨酸钠(Na2 WO4·2H2O)为原料,在简单的微波水热-煅烧条件下成功制备了形貌可控的交叉薄片状C/Bi2 WO6微晶.研究了反应体系中前驱物的不同摩尔比对产物的结构形貌以及光催化性能的影响.采用X-射线衍射仪(XRD)、EDS能谱分析、扫描电子显微镜(SEM),Perkin Elmer Larnbda 950型紫外可见漫反射光谱仪和康塔公司NOVA 2200e型表面空隙度分析仪分别对产物的结构、形貌,光学性能以及氮吸附-脱附等温线进行表征.结果表明:当前驱物葡萄糖,硝酸铋和钨酸钠的摩尔比为1∶10∶5时,合成了形貌可控且具有较好可见光催化性能的C/Bi2WO6微晶,其禁带宽度为3.055 eV,在可见光照射240 min后对罗丹明B的降解效率可达到94.8;.  相似文献   

15.

Abstract  

The title compound, C18H20N2O2, a potential pharmaceutical agent, crystallizes in the monoclinic P21/n space group with unit cell parameters a = 11.157 (7) ?, b = 8.776 (6) ?, c = 16.460 (11) ?, β = 103.08 (3)°. The tetrahydroquinoline ring system formed by the fusion of the benzene ring and the piperidine ring via two carbon atoms is coplanar, with the later adopting a sofa conformation. The pyrrolidine group in position 4 adopts an envelope conformation. Dimers related by inversion centers and linked by hydrogen bonds of the type N–H···O form cycles described by the graph set R22(16). Additionally, the dimers connect through weak hydrogen bonds of the type C–H···O with graph set C(10) to form chains extending along [001].  相似文献   

16.
The mono‐hydrate phase as well as the water‐free RbD2PO4 (DRDP) is obtained by crystal growth from fully deuterated aqueous solution. Its crystal structure was determined by combined neutron and X‐ray single crystal diffraction. It consists of double layers of PO4 tetrahedra with D2O planes in between. The PO4 groups are linked by fully ordered deuterium bonds O‐D‐O. RbD2PO4.D2O dehydrates below 329(5)K and undergoes a phase transition to RbD2PO4 (DRDP).  相似文献   

17.
采用基于第一性原理的密度泛函理论和Hubbard修正方法(DFT+U)计算了多铁材料InFeO3和In2FeCrO6的电子结构和光吸收性质.计算结果表明,Cr掺杂InFeO3的形成能比BiFeO3要低,相对容易完成掺杂,In2FeCrO6带隙宽度相对本征InFeO3没有明显的变化,但能带的色散变小,促进了可见光吸收.通过态密度分析可知,In2FeCrO6中CBM的Fe-3d能级比InFeO3的CBM的Fe-3d能级占据数变小,局域化程度降低,能带变得比较平缓.在InFeO3和In2FeCrO6体系中,Fe和Cr的化合价约为1.7+,Fe-O和Cr-O之间的库伦作用和成键程度差异性不大,导致两者的带隙变化不明显.光吸收谱分析表明,在入射光能量2.1~2.75eV范围内,Cr的掺入改善了InFeO3的可见光的吸收性能.  相似文献   

18.
A 1:2:2 complex of diaza crown ether 1,4,10,13-tetraoxa-7,16-diazacyclooctadecane, anthraflavic acid (2,6-dihydroxyanthraquinone) and water has been synthesized. The crystal is triclinic, P1, with a = 7.705(2), b = 10.871(2), c = 11.540(2) Å, = 100.40(2), = 91.38(2), = 98.01(2)°, Z = 1, and Dcalc = 1.375 mg m–3. The main feature of the crystal structure is the formation of a supramolecular sheet by hydrogen bonding of the anthraflavic monoanions, not only head-to-tail through the hydroxyl oxygens, but sideways through the quinone oxygens. This complex represents an intermediate case between total transfer of protons of a hydroxy-guest to crown N-atoms, and no transfer.  相似文献   

19.
为降低0.6SrTiO3-0.4LaAlO3(简称6ST-4LA)微波介质陶瓷的烧结温度,采用固相反应法,研究了B2O3对其结构与性能的影响.结果表明:添加B2O3可有效地降低6ST-4LA陶瓷的烧结温度,由1550℃降至1450℃;主晶相仍为赝立方钙钛矿结构固溶体,但有第二相的出现,其含量随着B2O3添加量的增加先降低后升高.当B2O3添加量为0.50wt;在1450℃下烧结时,6ST-4LA陶瓷获得最佳微波介电性能:εr=44.46,Q·f=51127 GHz,τf=-2.3×106/℃.  相似文献   

20.
Abstract  [Na(H2O)2(C18H15O6SO3)]2 was synthesized by sulfated 5-hydroxy-6,7,4′-trimethoxyisoflavone with concentrated sulfuric acid. Single-crystal X-ray diffraction study indicates that it is a dimeric centrosymmetric species. The coordination polyhedron of each Na(I) atom exhibits a distorted trigonal bipyramidal geometry. The dimeric units are linked by intermolecular hydrogen bonds C–H⋯π, C–H⋯O and O–H⋯O to result in a three-dimensional framework. Graphical Abstract  [Na(H2O)2(C18H15O6SO3)]2 was synthesized by sulfated 5-hydroxy-6,7,4′-trimethoxyisoflavone with concentrated sulfuric acid. The coordination polyhedron of each Na(I) atom exhibits a distorted trigonal bipyramidal geometry. The dimeric centrosymmetric units are linked by intermolecular hydrogen bonds C–H⋯π, C–H⋯O and O–H⋯O to result in a three-dimensional framework. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

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