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1.
通过简便的蒸发方法得到了2种碱金属磺酸盐非线性光学(NLO)晶体,即Li(NH2SO3)和Na(NH2SO3)。Li(NH2SO3)以极性空间群Pca21(编号29)结晶。Li(NH2SO3)的结构可以描述为由[LiO4]7-多面体通过共角连接与NH2SO3-四面体相互连接而形成的三维网络。Na(NH2SO3)以极性空间群 P212121(编号 19)结晶。Na(NH2SO3)的结构可以描述为由扭曲的[NaO6]11-八面体通过共角连接与 NH2SO3-四面体相互连接而形成的三维网络。紫外可见近红外光谱表明,Li(NH2SO3)和 Na(NH2SO3)分别具有 5.25 和 4.81eV 的大光学带隙。粉末二次谐波发生(SHG)测量显示,Li(NH2SO3)和 Na(NH2SO3)的 SHG 强度分别为 KH2PO4的 0.32 倍和 0.31倍。第一原理计算证实,非线性光学性能主要来自氨基磺酸阴离子和碱金属氧阴离子多面体的协同作用。  相似文献   

2.
不同稀土改性SO42-/ZrO2催化剂的结构与性能表征   总被引:3,自引:0,他引:3  
Solid superacid catalyst SO42-/ZrO2 was modified by different rare earth compounds and applied to the esterification of acetic acid and n-butanol. The effects of rare earth elements loading on the catalytic properties were studied and the correlation between the structure and properties was investigated by means of XRD, IR, UV, DTA and TG. The results show that the (NH4)2Ce(NO3)6 modification can enhance catalytic activity more and exhibit better stability than the other two compounds La(NO3)3 and Ce(NO3)3. Meanwhile,(NH4)2Ce(NO3)6 modification can restrain the loss of SO42- efficiently. The optimum calcination temperature and molar ratio of Ce(NH)∶Zr for SO42-/ZrO2 catalyst modified by (NH4)2Ce(NO3)6 are 450 ℃ and 2, respectively.  相似文献   

3.
采用原位溶剂热法合成了2种混合有机阳离子杂化甲酸盐(CH(NH2)2)[RE (HCOO)4](RE=Y、Er)。这2种材料是同构的(手性空间群C2221),并具有有趣的类钙钛矿结构。进行了包括线性和非线性光学特性在内的光物理研究。(CH(NH2)2)[Y(HCOO)4]和(CH(NH2)2)[Er(HCOO)4]分别表现出5.59和5.61 eV的宽光学带隙,对应于222和221 nm的紫外吸收边缘。粉末倍频测量表明,(CH(NH2)2)[Y(HCOO)4]和(CH(NH2)2)[Er(HCOO)4]的倍频效应分别是基准KH2PO4(KDP)的0.32和0.37倍。测量得到(CH(NH2)2)[Y(HCOO)4]和(CH(NH2)2)[Er(HCOO)4]的双折射率分别为0.013和0.015。第一性原理研究表明,2个π共轭的(CH(NH2)2)+和HCOO-基团是光学性质的主要贡献者。  相似文献   

4.
采用原位溶剂热法合成了2种混合有机阳离子杂化甲酸盐(CH (NH2)2)[RE (HCOO)4](RE=Y、Er)。这2种材料是同构的(手性空间群C2221),并具有有趣的类钙钛矿结构。进行了包括线性和非线性光学特性在内的光物理研究。(CH (NH2)2)[Y (HCOO)4]和(CH (NH2)2)[Er (HCOO)4]分别表现出5.59和5.61 eV的宽光学带隙,对应于222和221 nm的紫外吸收边缘。粉末倍频测量表明,(CH (NH2)2)[Y (HCOO)4]和(CH (NH2)2)[Er (HCOO)4]的倍频效应分别是基准KH2PO4(KDP)的0.32和0.37倍。测量得到(CH (NH2)2)[Y (HCOO)4]和(CH (NH2)2)[Er (HCOO)4]的双折射率分别为0.013和0.015。第一性原理研究表明,2个π共轭的(CH (NH2)2)+和HCOO-基团是光学性质的主要贡献者。  相似文献   

5.
trans-[XRu(py)4(NO)]2+(X=Cl,Br)与等物质的量的NaN3在甲醇中反应后生成中间体trans-[XRu(py)4(CH3OH)]+,它再与过量的Na[N(CN)2]或K[C(CN)3]反应后生成单核配合物trans-XRu(py)3L(X=Cl,Br,L=N(CN)2-,C(CN)3-)。单核配合物XRu(py)4L与[X′Ru(py)4(CH3OH)]+进行分子组装,生成了一系列双核钌配合物trans-[X(py)4Ru(μ-L)Ru(py)4X′]+。用等物质的量的NOBF4或(NH4)2[Ce(NO3)6]氧化这些RuRu双核钌配合物,得到了一系列RuRu混合价配合物trans-[X(py)4Ru(μ-L)Ru(py)4X′]2+。N(CN)2-桥联的RuRu混合价配合物在近红外区存在中等强度的吸收,起源于混合价态间的电荷跃迁(Intervalence Charge Transfer,简称为IVCT),且其最大吸收波长随着溶剂极性的改变而发生变化,它们属于Class Ⅱ类型的混合价化合物;而C(CN)3-桥联的RuRu混合价配合物在近红外的吸收要强得多,且溶剂极性的改变对IVCT最大吸收波长基本无影响,它们属于介于价态定域与离域之间的混合价配合物。  相似文献   

6.
鲁晓明  宋富根  王波  李丽 《无机化学学报》2005,21(11):1687-1690
Cis-dioxo-catecholatotungsten(Ⅴ) complex (NH2CH2CH2NH3)4[WO2(OC6H4O)2]2(NH3CH2CH2NH3)·H2O (1) was synthesized at room temperature by the reaction of tetrabutyl ammonium decatungstate with catechol in the mixed solvent of CH3OH, CH3CN and NH2CH2CH2NH2. The crystal structure of complex was determined by X-ray diffraction structural analysis. The results show that complex belongs to monoclinic system with space group P21/c,a=0.712 8(3) nm, b=3.082 3(11) nm, c=0.982 8(4) nm, β=102.639(6)°, V=2.106 8(14) nm3, Z=2, R1=0.062 8, wR2=0.183 7. Compared the complex with its analogous complexes (NH2CH2CH2NH3)3[MoO2(OC6H4O)2], it is found that the coordination structure of W have no changes in the processing of electron transfer of tungsten-containing enzymes from the result of the similarity of the EPR spectra of the complexes and flavoenzyme from milk. CCDC: 272937.  相似文献   

7.
通过无机碘盐(MIn)与 cis-[Fe(CO)4I2]反应制备了 5 个盐类化合物 fac-M[Fe(CO)3I3]n (Mn+=Na+ (1),K+ (2),Mg2+ (3),Ca2+ (4),NH4+ (5)),探讨了阳离子Mn+fac-[Fe(CO)3I3]-阴离子的稳定性和细胞毒性的影响。通过傅里叶变换红外光谱(FTIR)监测,发现盐 1~5在 DMSO、D2O、生理盐水等介质中均能缓释 CO,其释放动力学符合一级反应动力学模型;还发现溶液中碘离子的浓度和酸度对该阴离子的缓释CO性能也具有调节作用。通过噻唑蓝(MTT)实验评估了盐1~5对膀胱癌细胞的毒性,其24 h半抑制浓度(IC50)在 25~43 μmol·L-1。与有机铵阳离子类的盐化合物相比,盐1~5在含水介质中的释放 CO速率下降,毒性亦有下调。研究还发现这类fac-[Fe(CO)3I3]-阴离子在缓释CO的同时释放碘自由基,并能导致线粒体活性氧(ROS)水平、Parkin蛋白表达均上调。铁死亡抑制剂(Ferrostatin-1和Liproxstatin-1)试验结果表明这类化合物可能引发铁死亡通路并促进肿瘤细胞死亡。  相似文献   

8.
Reaction of (NH4)2[WOS3] with CuI and 4-tert-butylpyridine (4-bpy) in EtOH afforded a tetranuclear neutral cluster [WOS3Cu3I(4-bpy)3]·0.25EtOH. This compound was characterized by elementary analysis, IR, 1H NMR, TGA, and its crystal structure was determined by X-ray single crystal diffraction. It belongs to monoclinic, space group P2/c with a=2.220 9(2) nm, b=1.364 66(11) nm, c=2.490 6(2) nm, β=104.953(2)°, V=7.292 9(12) nm3, Z=4. The title compound may be viewed as having a half-open cubane-like structure in which three [Cu(4-bpy)]+ units are linked by a triply-bridging [WOS3]2- unit and a doubly-bridging iodine atom. CCDC: 266412.  相似文献   

9.
马运声  王君  袁荣鑫 《无机化学学报》2008,24(12):2043-2046
Azide-containing coordination polymers have received considerable attention for the construction of new molecule-based magnets. A three dimensional heteronuclear Mn-Na compound [MnNa(N3)4(C5H5N)4] was obtained by reaction of [Mn3O(O2CCH3)6(py)3]ClO4 and NaN3 in pyridine solvents. The title compound crystallizes in monoclinic space group C2/c, a=1.536 6(2), b=1.045 3(2), c=1.576 3(2) nm, β=90.309(3)°, V=2.531 8(6) nm3, Z=4. In the structure, each Mn3+ and Na+ ion coordinated with four N atoms from four N3- and two N atoms from two pyridine molecules. Each pair of Mn3+ and Na+ ion are linked by N3- bridges into a 3D polymer with PtS topology. CCDC: 706250.  相似文献   

10.
用1,4,7,10,13-五氮十五烷(cpad)作为端基配体,合成了2个同构化合物[{Ni(cpad)}3M(CN)6]2[M(CN)6](ClO4)3·6H2O (M=Cr3+,1;Fe3+,2),其中[M(CN)6]3-通过氰基桥联配位,4个[Ni(cpad)]2+阳离子形成四核簇[{Ni(cpad)}3M(CN)6]3+,游离的[M(CN)6]3-和ClO4-为平衡阴离子。晶体参数如下:1,三方晶系,P3c1空间群,a=1.5144 1(18) nm,c=3.080 7(6) nm,V=6.118 9(15) nm3,Z=2;2,三方晶系,P3c1空间群,a=1.4976 2(17) nm,c=3.087 8(5) nm,V=5.997 6(14) nm3,Z=2。变温磁化率显示在四核簇内氰基桥联的金属离子之间存在铁磁相互作用。  相似文献   

11.
Raman and FTIR spectra of guanidinium zinc sulphate [C(NH2)3]2Zn(SO4)2 are recorded and the spectral bands assignment is carried out in terms of the fundamental modes of vibration of the guanidinium cations and sulphate anions. The analysis of the spectrum reveals distorted SO42− tetrahedra with distinct S–O bonds. The distortion of the sulphate tetrahedra is attributed to Zn–O–S–O–Zn bridging in the structure as well as hydrogen bonding. The CN3 group is planar which is expressed in the twofold symmetry along the C–N (1) vector. Spectral studies also reveal the presence of hydrogen bonds in the sample. The vibrational frequencies of [C(NH2)3]2 and HC(NH2)3 are computed using Gaussian 03 with HF/6-31G* as basis set.  相似文献   

12.
Reaction between Mo(CO)6 and p-C5NH4SO3Na (1:2 (Mo: p-C5NH4SO3Na) stoichiometric ratio) gave the trans-Mo(CO)4(p-C5NH4SO3Na)2 complex, (1), in 80% yield. Complex (1) has been characterized by FTIR, 1H and 13C NMR spectroscopy. Complex (1) has most likely an idealized D4h geometry with trans N-bound p-C5NH4SO3Na ligands.  相似文献   

13.
14.
Twisted Tetrahedra Chains 1[Li(NH2)4/2?] in the Structure of the Hexagonal Modification of Cesium Lithium Amide, CsLi(NH2)2 The ternary amides, CsLi(NH2)2 (dimorphous) and CsLi2(NH2)3, were prepared by reaction of the metals with ammonia in high pressure autoclaves. The structure of the hexagonal modification of CsLi(NH2)2 was established inclusive the hydrogen atom positions from single crystal x-ray data. The compound crystallizes in the space group P6222 with N = 3. The lattice parameters are a = 6.331(1) Å and c = 8.410(1) Å. Lithium ions occupy distorted nitrogen tetrahedra. These tetrahedra are connected by translocated edges along [001]. The cesium ions combine the equally oriented chains [Li(NH2)4/2?]. The amide ions are twisted out of the hexagonal aa-plane. If we assume sp3-hybridized valence electrons of the nitrogen atoms the bonding interaction between free electron pairs and lithium ions are thereby strenghtened.  相似文献   

15.
The first fluorosulfonic ultraviolet (UV) nonlinear optical (NLO) material, C(NH2)3SO3F, is rationally designed by taking KBe2BO3F2 (KBBF) as the parent compound. C(NH2)3SO3F features similar topological layers as KBBF by replacing inorganic (BO3)3? with organic C(NH2)3+ trigonal units and BeO3F with SO3F? tetrahedra. Therefore, C(NH2)3SO3F is a metal‐free UV NLO crystal. Benefiting from the coplanar configuration of the C(NH2)3+ cationic groups, it possesses a large SHG response of 5×KDP and moderate birefringence of 0.133@1064 nm. Besides, it has a short UV cutoff edge of 200 nm. The calculated results reveal the shortest SHG phase‐matching wavelengths can reach 200 nm. These findings highlight the exploration of metal‐free compounds as nontoxic and low‐cost UV NLO materials as a new research area.  相似文献   

16.
Two new borosulfates were obtained either by an open vessel synthesis from sulfuric acid and B(OH)3, yielding (NH4)3[B(SO4)3] or from solvothermal synthesis in oleum enriched sulfuric acid and B(OH)3, yielding Sr[B2(SO4)4]. (NH4)3[B(SO4)3] crystallizes homeotypic to K3[B(SO4)3] in space group Ibca (Z = 8, a = 728.58(3) pm, b = 1470.84(7) pm, c = 2270.52(11) pm), comprising open branched vierer single chains {1[B(SO4)2(SO4)2/2]3–}. Sr[B2(SO4)4] crystallizes as an ordered variant of Pb[B2(SO4)4] in space group Pnna (Z = 4, a = 1257.4(4) pm, b = 1242.1(4) pm, c = 731.9(2) pm), consisting of loop branched vierer single chains {1[B(SO4)4/2]2–}. Vibrational spectroscopy confirms both refined structure models. Thermal analysis of the dried powders, showed a decomposition towards the binary and ternary components, whereas a thermal treatment in the presence of the mother liquor promotes a decomposition of Sr[B2(SO4)4] towards Sr[B2O(SO4)3].  相似文献   

17.
Synthesis, crystal structure, DSC characterization, dielectric and Raman measurements are given for a new mixed solution K0.84(NH4)1.16SO4Te(OH)6 (KNST). X-ray studies showed that the title compound crystallizes in the monoclinic system (P21/c) with the following parameters: , , , β=120.17(2)° and Z=4. The structure can be regarded as being built of isolated TeO6 octahedra, SO4 tetrahedra and cations. The main feature of this structure is the coexistence of two types of hydrogen bonds OHO and NHO ensuring the cohesion of the crystal. Crystals of K0.84(NH4)1.16SO4Te(OH)6 undergo two endothermic peaks at 425 and 480 K and a shoulder at 470 K. These transitions detected by DSC and analyzed by dielectric measurements using the impedance and modulus spectroscopy techniques. Raman scattering measurements on K0.84(NH4)1.16SO4Te(OH)6 material taken between 300 and 620 K are reported in this paper. The spectra indicate clearly two phase transitions.  相似文献   

18.
Synthesis and crystal structure of a new structure type of mixed Cr(III)/Cr(VI) chromates is reported. NH4Cr(CrO4)2 was prepared from CrO3 in the presence of (NH4)2Ce(NO3)6. Since this is the first preparation of mixed valence ternary chromium oxides from aqueous solution, a reaction pathway for this synthesis is suggested. The crystal structure of NH4Cr(CrO4)2 has been determined from three-dimensional X-ray data collected at low temperature, 173 K. The structure belongs to the orthorhombic space group Pnma, with a=14.5206(10), b=5.4826(4), and Z=4. The title compound consists of corner-sharing chromium(III) octahedra and chromium(VI) tetrahedra forming a three-dimensional network with the composition [Cr(CrO4)2]nn-, containing channels in which zigzag rows of ammonium ions balance the net charge.  相似文献   

19.
Mixed crystals of Li[Kx(NH4)1−x]SO4 have been obtained by evaporation from aqueous solution at 313 K using different molar ratios of mixtures of LiKSO4 and LiNH4SO4. The crystals were characterized by Raman scattering and single-crystal and powder X-ray diffraction. Two types of compound were obtained: Li[Kx(NH4)1−x]SO4 with x?0.94 and Li2KNH4(SO4)2. Different phases of Li[Kx(NH4)1−x]SO4 were yielded according to the molar ratio used in the preparation. The first phase is isostructural to the room-temperature phase of LiKSO4. The second phase is the enantiomorph of the first, which is not observed in pure LiKSO4, and the last is a disordered phase, which was also observed in LiKSO4, and can be assumed as a mixture of domains of two preceding phases. In the second type of compound with formula Li2KNH4(SO4)2, the room-temperature phase is hexagonal, symmetry space group P63 with cell-volume nine times that of LiKSO4. In this phase, some cavities are occupied by K+ ions only, and others are occupied by either K+ or NH4+ at random. Thermal analyses of both types of compounds were performed by DSC, ATD, TG and powder X-ray diffraction. The phase transition temperatures for Li[Kx(NH4)1−x]SO4x?0.94 were affected by the random presence of the ammonium ion in this disordered system. The high-temperature phase of Li2KNH4(SO4)2 is also hexagonal, space group P63/mmc with the cell a-parameter double that of LiKSO4. The phase transition is at 471.9 K.  相似文献   

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