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1.
等人在LaCl_3-CH_3CONH_2-H_2O三元体系30℃时的研究中得到了一个三元复合物(前文文献[2]),我们对同一体系作了较为仔细的研究之后发现,该复合物的组成并非该作者报导的LaCl_3·5CH_3CONH_2·5H_2O,而是LaCl_3·4CH_3CONH_2·5H_2O。我们还对该复合物进行了初步研究,测定了密度,拍摄了显微照片和X-光粉末衍射图,并计算了d/n值(见前文)。本文作为前文工作的继续,对LaCl_3·4CH_3CONH_2·5H_2O-H_2O二元体系进行了研究。  相似文献   

2.
Summary The crystal structure of K3SbS4·4 1/2 H2O, monoclinic, P21/c-C 5 2h ,a=12.732(3),b=7.720(2),c=13.928(4) Å, =90.19(1)°,V=1369.0(5) Å3,Z=4, has been determined from X-ray single crystal data and refined by least-squares methods toR=0.031 for 3 024 reflections. The structure is built up from KS4 – 5(H2O)3 – 5 polyhedra and SbS4 tetrahedra (Sb-S=2.327 Å) which are three-dimensionally linked. The water molecules are bonded to two or three K+ ions and form exclusively O-H ... S-type hydrogen bonds. One of the five crystallographically different water molecule sites is due to space limitations only half occupied.
Die Kristallstruktur von K3SbS4·4 1/2 H2O
Zusammenfassung Die Kristallstruktur von K3SbS4·4 1/2 H2O, monoklin, P21/c-C 5 2h ,a=12.732(3),b=7.720(2),c=13.928(4) Å, =90.19(1)°,V=1369.0(5) Å3,Z=4, wurde mit Röntgen-Einkristalldaten bestimmt und für 3 024 Reflexe aufR=0.031 verfeinert. Die Kristallstruktur ist aus dreidimensional verknüpften KS4 – 5(H2O)3 – 5-Polyedern und SbS4-Tetraedern (Sb-S=2.327 Å) aufgebaut. Die Wassermoleküle sind an zwei bis drei Kaliumionen gebunden und bilden ausschließlich Wasserstoffbrücken des Typs O-H...S aus. Eine der fünf kristallographisch verschiedenen H2O-Lagen ist aus Platzmangel nur zur Hälfte besetzt.
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3.
杂多化合物在催化、医药、材料及光化学等方面具有广泛的应用前景 [1~ 4 ] ,其中钼磷多金属氧酸盐具有优异的氧化催化性能 [5,6 ] .近年来合成的新奇结构的钼磷多金属氧酸盐中已测定结构的有含帽[7,8] 和非帽[9~ 12 ] 系列 .本文利用水热法合成了未见文献报道的结构新颖的夹心型磷钼多金属氧酸盐[( CH3CH2 ) 4N]4 H3O{Na[( HMo2 O5) 3( HPO4 ) ( H2 PO4 ) 3]2 }· ( H2 PO4 ) 2 · 1 0 H2 O,并测定了其晶体结构 .1 实验与晶体结构分析1 .1 仪器与试剂 元素 Na用美国原子吸收分光光度计测定 ;C,H和 N用 Perkin- Elmer 2 4 0…  相似文献   

4.
刘志宏  高世扬  胡满成  夏树屏 《中国化学》2002,20(12):1519-1522
IntroductionTherearemanykindsofmagnesiumborates ,bothnaturalandsynthetic .Aboratedoublesalt (2MgO·2B2 O3 ·MgCl2 · 14H2 O)namedchloropinnoitewasob tainedfromthenaturalconcentratedsaltlakebrine .1Inordertofindtheformingrelationbetweenthedoublesaltandmagnesium bora…  相似文献   

5.
After a short survey of what is the present state of the cyclophosphates associated with the organic molecule NH2(CH2)4NH2, we report chemical preparation and crystal structure for a new example of such compounds. [NH3(CH2)4NH3]2P4O12.2H2O is monoclinic (S.G. : P21/n), with Z = 2 and the following unit-cell parameters : a = 7.6728(8) Å, b = 18.962(3) Å, c = 7.9789(9) Å β = 111.751(9)°. Bidimensional layer arrangement of P4O12 rings connected to the water molecules thanks to weak H-bonds run parallel to the ab plane. The organic groupements located between these inorganic planes perform the three-dimensional cohesion by NH····O hydrogen bonds.  相似文献   

6.
7.
三元体系Yb(ClO_4)_3·3H_2O·18C6-CH_3COCH_3(25℃)相平衡研究李谦定,陈红娟任德厚(西安石油学院化工系710061)(西北大学化学系710069)采用在一定溶剂中按某种摩尔比混合盐和醚,经适当后处理来制备固态稀土盐冠醚...  相似文献   

8.
9.
2MgO·2B_2O_3·MgCl_2·14H_2O-H_3BO_3-H_2O体系30℃相平衡   总被引:5,自引:0,他引:5  
用相平衡方法研究了2MgO·2B_2O_3·MgCl_2·14H_2O-H_3BO_3-H_2O在30 ℃ 不同浓度H_3BO_3水溶液中的溶解转化产物及其溶解度。结果表明,氯柱硼镁石的 溶解转化产物,在H_3BO_3质量分数≤2.50%时为多水硼镁石;在2.50% ~ 5. 00%H_3BO_3范围时为库水硼镁石;当H_3BO_3量在5.00% ~ 5.60%之间时为章氏硼 镁石;而当H_3BO_3量≥5.60%时为三方硼镁石。提出了溶解相转化机理。  相似文献   

10.
11.
《Solid State Sciences》2004,6(2):229-233
Two new organically templated zinc selenites MIL-86 or [H2N(CH2)2NH2]2·Zn4(SeO3)4 and MIL-87 or [H3N(CH2)3NH3]4·Zn4(SeO3)8 have been prepared by the reaction of ZnO with SeO2 under hydrothermal conditions in the presence of organic amines. Crystal data: MIL-86, monoclinic, space group P21/n, a=6.7712(4) Å, b=9.4520(5) Å, c=8.0295(4) Å, β=113.601(1)°, V=470.91(4) Å3; MIL-87, orthorhombic, space group Pbcm, a=8.8311(3) Å, b=7.8391(2) Å, c=16.2992(4) Å, V=1128.36(6) Å3. MIL-86 combines the structural features of templated networks and coordination polymers. Its structure is built up from ZnO3N tetrahedra and SeO3 pseudo-pyramids as the polyhedral building units. The ZnN bond corresponds to a direct link between zinc and the ethylenediamine template. In the other hand, MIL-87 is built up from chains of vertex-linked ZnO4 and SeO3 building units crosslinked by 1,3-diammonium propane cations. These structures are understood by comparison with the already known organically templated zinc phosphites.  相似文献   

12.
It was earlier found from nuclear quadrupole resonance (NQR) measurements and computer modeling that -Bi2O3, Bi3O4Br and mixed oxides Bi2O3· 2Al2O3, Bi2O3· 2Ga2O3, Bi2O3· 3GeO2, and 2Bi2O3· 3GeO2exhibit local ordered magnetic fields from 30 to 200 G. It thus follows that these compounds are not diamagnets in a conventional sence of the word. With the aim of revealing previously unknown magnetic properties in bismuth(III) oxide-based Main Group element compounds, the mixed bismuth–boron oxides 2Bi2O3· B2O3, 3Bi2O3· 5B2O3, and Bi2O3· 3B2O3were prepared and studied using 209Bi NQR. The quadrupole interactions of the 209Bi nuclei and their electronic environment were studied, the crystallochemical features of the compounds were discussed, and the conformity of the 209Bi results to the X-ray structure data was verified. The preliminary tests in the field of a permanent magnet showed that the resonance intensities increase in external magnetic fields, indicating that a magnetism of unknown nature develops in the titled compounds. It was found reasonable to continue studies of the magnetic properties of these compounds using single-crystal 209Bi NQR in external magnetic fields.  相似文献   

13.
In light of the important recent synthesis of a stable tetrasilacyclobutadiene dianion compound by Sekiguchi and co-workers and the absence of theoretical studies, ab initio methods have been used to investigate this dianion and a number of related species. These theoretical methods predict multiple minima for each compound, and most minima contain folded and bicyclic silicon rings. For (Si(4)H(4))(2-), (Si(4)H(4))(2-)·2Li(+), [Si(4)(SiH(3))(4)](2-)·2Li(+), [Si(4)(SiH(3))(4)](2-)·2Na(+), and [Si(4)(SiH(3))(4)](2-)·2K(+), respectively, the energetically lowest-lying structures are designated A-3 (C(2v) symmetry), B-8 (C(1) symmetry), C-1 (C(2) symmetry), D-1 (C(2) symmetry), and E-1 (C(2h) symmetry). None of these structures satisfies both the ring planarity and the cyclic bond equalization criteria of aromaticity. However, all of the representative NICS values of these lowest-lying structures are negative, indicating some aromatic character. Especially, structures C-1 and D-1 of C(2) symmetry effectively satisfy the criteria of aromaticity due to the slightly trapezoidal silicon rings, which are nearly planar with nearly equal bond lengths. SiH(3) substitution for hydrogen in (Si(4)H(4))(2-)·2Li(+) significantly reduces the degree of aromaticity, as reflected in the substantially smaller NICS absolute values for [Si(4)(SiH(3))(4)](2-)·2Li(+) than those of (Si(4)H(4))(2-) and (Si(4)H(4))(2-)·2Li(+). The aromaticity is further weakened in [Si(4)(SiH(3))(4)](2-)·2Na(+) and [Si(4)(SiH(3))(4)](2-)·2K(+) by replacing lithium with the sodium and potassium cations.  相似文献   

14.
The syntheses and crystal structures of the closely related but non-isostructural Cd2(C19H21N3O3F)4(H2O)2?·?4H2O (1) and Pb2(C19H21N3O3F)4?·?4H2O (2) are described, where C19H21N3O3F? is enrofloxacinate (enro). Both compounds contain centrosymmetric, binuclear, neutral complexes incorporating a central diamond-shaped M2O2 (M?=?Cd, Pb) structural unit. The Cd2+ coordination polyhedron in 1 is a CdO6 trigonal prism, including one coordinated water. The Pb2+ coordination polyhedron in 2 can be described as a very distorted square-based PbO5 pyramid, although two additional short Pb?···?O (<3.1?Å) contacts are also present. In the crystal of the cadmium complex, O–H?···?O hydrogen bonds lead to a layered structure. In the lead compound, O–H?···?O and O–H?···?N interactions lead to chains in the crystal. Crystal data: 1: C76H96Cd2F4N12O18, M r?=?1766.45, triclinic, P 1, a?=?12.185(2)?Å, b?=?12.306(3)?Å, c?=?14.826(3)?Å, α?=?68.15(3)°, β?=?70.28(3)°, γ?=?86.11(3)°, V?=?1938.2(7)?Å3, Z?=?1, T?=?298 K, R(F)?=?0.030, wR(F 2)?=?0.079. 2: C76H88F4N12O16Pb2, M r?=?1920.00, triclinic, P 1, a?=?12.0283(4)?Å, b?=?12.7465(4)?Å, c?=?13.0585(4)?Å, α?=?83.751(1)°, β?=?74.635(1)°, γ?=?81.502(1)°, V?=?1904.3(1)?Å3, Z?=?1, T?=?298?K, R(F)?=?0.021, wR(F 2)?=?0.049.  相似文献   

15.
标题配合物是由三齿配体Ⅳ,Ⅳ-二(2-苯并咪唑甲基)亚胺(IDB)与NiSO4·6H2O在甲醇-乙醇溶液中反应得到的紫色 晶体.X射线衍射测定了其单晶结构.结构分析表明,镍(Ⅱ)分别与两个IDB配体中的苯并咪唑的四个氮和胺基的两个 氮配位形成畸变的八面体构型.研究了纳米金和小牛胸腺DNA对配合物荧光的影响,探讨了配合物的荧光猝灭与恢复 的可能机理.  相似文献   

16.
以低浓度(30(wt)%)的双氧水制备了硫酸钠-过氧化氢-氯化钠加合物,各组分的含量均接近于理论值,其纯度为99.3%;在323K和333K下,研究了4Na2SO4*2H2O2*NaCl于碱性水溶液中的分解动力学.结果表明,在不同条件下,其分解均为一级反应;随着温度和pH的增加,其分解速率加快.置信水平为95%时k和C0的联合置信域均为椭圆形且面积较小,求得的参数精确度较高;优化出的模型能较准确地描述4Na2SO4*2H2O2*NaCl于碱性水溶液中的分解过程.  相似文献   

17.
Inorganic–organic hybrid compounds exhibit interesting properties in several application areas. In this regard, chemical preparation and characterization by X-ray diffraction, thermal analysis, and IR spectroscopy are given for a new organic cation diphosphate [4-CH3OC6H4CH2NH3]4P2O7·6H2O. This later crystallizes in a C2/c unit cell with a = 38.238(6)Å, b = 6.453(1)Å, c = 16.942(7)Å; β = 97.60(4)°; Z = 4; and V = 4144(2)Å3 and Dx = 1.377 g·cm?3. Its crystal structure has been determinated and refined to R = 0.044, using 7978 independent reflections. This atomic arrangement consists of inorganic layers built up from P2O7 4? anions and water molecules. On these layers, which are parallel to the (b, c) planes, the (4-CH3OC6H4CH2NH3)+ cations are anchored through multiple hydrogen bonds.  相似文献   

18.
The solubility of 10 lanthanide elements and of scandium is solid Bi2Ti4O11 has been determined using Raman spectroscopy and X-ray diffraction. The data obtained were used to construct a diagram of solubility as a function of the ionic radii of bismuth and the lanthanide elements. The thermal stability of the solid solutions as a function of temperature and duration of thermal treatment has been qualitatively established.  相似文献   

19.
[(CH3)2NH2]3[NSiMo12O40]·2DMF·4H2O的合成和晶体结构   总被引:5,自引:0,他引:5  
电荷转移盐;[(CH3)2NH2]3[NSiMo12O40]·2DMF·4H2O的合成和晶体结构  相似文献   

20.
稀土有机氢化物n-C_4H_9NdH_2·3LiOCH_3的研究   总被引:2,自引:2,他引:0  
金属有机氢化物是计量和催化反应的重要中间体。自1981年Evans首次合成并鉴定了稀土有机氢化物以来,对它的研究工作得到了相当快的发展。近年来,相继报道了几种稀土有机氢化物的合成方法,并研究了它们的化学性质。研究结果表明,稀土有机氢化  相似文献   

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