Die Ammonolyse von (NH4)2GeF6. Darstellung und Struktur von NH4[Ge(NH3)F5]

Ammonolysis Reaction of (NH₄)₂GeF₆. Synthesis and Structure of NH₄[Ge(NH₃)F₅] (NH₄)₂GeF₆ reacts with ammonia to yield NH₄[Ge(NH₃)F₅] at 280°C. The reaction path was elucidated by in situ time and temperature resolved X-ray powder diffraction. NH₄[Ge(NH₃)F₅] crystallizes isostructurally to NH₄[Si(NH₃)F₅] in the tetragonal space group P4/n (No. 85) with lattice constants a = 619.41(1) pm and c = 724.70(1) pm. The germanium atom is coordinated by five fluorine atoms and the nitrogen atom of the ammonia molecule. The ammonium cation is located on the Wyckoff position (2 a) in P4/n. The crystal structure is stabilized by extensive hydrogen bonding.     

Darstellung und Struktur von Sn(NH2)2F2

Synthesis and Structure of Sn(NH₂)₂F₂ Diamido-difluoro-tin Sn(NH₂)₂F₂ can be produced by ammonolysis from (NH₄)₂SnF₆ at 613 K. The compound is a product from Sn(NH₃)₂F₄ formed during the ammonolysis reaction. Sn(NH₂)₂F₂ crystallizes in space group C2/m (No. 12) with lattice constants a = 1070.18(7), b = 325.38(3) pm, c = 505.02(3) pm and β = 105.728(3)° (V = 169.271(6) · 10⁶ pm³) containing two formula units per unit cell. Data refinement by the Rietveld method yields a Bragg R-value of R_Bragg = 0.0514 (Profile R-value R_wp = 0.177). Tin is octahedrally coordinated by two fluorine atoms and for amido groups. The octahedra are connected to one-dimensional strings by edge sharing. The NH₂ groups are in the bridging position whilst the fluorine atoms are terminal.     

NH4VO3在NH4H2PO4-H2O和(NH4)3PO4-H2O体系中的溶解度

采用等温溶解法测定了偏钒酸铵(NH₄VO₃)在NH₄H₂PO₄-H₂O和(NH₄)₃PO₄-H₂O体系中T = 298.15-328.15 K时的溶解度以及溶液的密度和pH值。结果表明, NH₄VO₃的溶解度随着(NH₄)₃PO₄或NH₄H₂PO₄溶液浓度的增大,先降低后升高,这是由于同离子效应、化学反应平衡及离子活度的共同作用。比较T = 298.15K时, NH₄VO₃分别在NH₄H₂PO₄-H₂O、(NH₄)₂HPO₄-H₂O和(NH₄)₃PO₄-H₂O体系中溶解度,发现在相同的磷酸盐浓度下, NH₄VO₃的溶解度在NH₄H₂PO₄-H₂O体系中最大,在(NH₄)₃PO₄-H₂O体系中居中,在(NH₄)₂HPO₄-H₂O体系中最小。进一步地,在T = 298.15 K和磷酸盐浓度C = 0.5 mol·kg^-1时,结合pH值和反应溶度积常数K_SP等计算三个体系中的平均离子活度系数(γ_±),发现γ_±值在(NH₄)₂HPO₄-H₂O体系中最大,在(NH₄)₃PO₄-H₂O体系中居中,在NH₄H₂PO₄-H₂O体系中最小,与溶解度规律一致。     

Synthese und Kristallstruktur von Na2Zn(OH)4

Synthesis and Crystal Structure of Na₂Zn(OH)₄ Crystallization from saturated sodium hydroxozincate solutions yields colourless platelets of crystals of Na₂Zn(OH)₄. The X‐ray structure determination on these crystals was successful including all hydrogen positions. P2₁/n, Z = 4, a = 7.959(3) Å, b = 6.534(1) Å, c = 8.501(3) Å, β = 93.97(3)°, N(F²_o ° 2σ F²_o) = 1668, N(Var.) = 81, R₁/wR₂ = 0.043/0.107. Na₂Zn(OH)₄ crystallizes in a layered structure. Alternate layers contain Na⁺ in octahedral and Zn²⁺ in tetrahedral coordination by OH^–.     

Synthese und Kristallstruktur von (PPh4)2Se6

Synthesis and Crystal Structure of (PPh₄)₂Se₆ (PPh₄)₂Se₆ has been prepared by the reaction of selenium with K₂Se₂ in dimethylformamide solution in the presence of K₃[Mn(CN)₆] and PPh₄Br, forming black crystal needles. According to the crystal structure determination the compound consists of PPh⁺₄ ions and chainlike hexaselenide ions. Space group P6 , Z = 2,4683 Observed unique reflections, R = 0.066. Lattice dimensions at ?90°C: a = 951.0, b = 1094.8, c = 2137.4 pm, α = 82.66°, β = 83.36°, γ = 89.96°.     

Synthese und Kristallstruktur von [Cr(NH3)6][Cr(NH3)2F4][BF4]2

Synthesis and Crystal Structure of [Cr(NH₃)₆][Cr(NH₃)₂F₄][BF₄]₂ The action of ammonium fluoride on a mixture of boron and chromium in a sealed Monel ampoule at 300 °C yields single crystals of [Cr(NH₃)₆][Cr(NH₃)₂F₄][BF₄]₂. The crystal structure (tetragonal, P4/mbm, Z = 2, a = 1056.0(1), c = 781.7(1) pm; R₁ = 0.0414; wR₂ = 0.1087 for 411 reflections with I₀ > 2σ(I)) contains [Cr(NH₃)₆]³⁺ and [Cr(NH₃)₂F₄]^– octahedra and twice as many [BF₄]^– tetrahedra that are arranged in a quadrupled super‐structure of the CsCl‐type of structure.     

Zeit- und temperaturaufgelöste Röntgenpulverdiffraktometrie: Die Reaktion von (NH4)2SnF6 mit Ammoniak

Time and Temperature Resolved in situ X-Ray Powder Diffractometry. The Reaction of (NH₄)₂SnF₆ with Ammonia The thermal decomposition of (NH₄)₂SnF₆ under an atmosphere of ammonia is reported. The complicated reaction paths were illucidated by time and temperature resolved in situ x-ray powder diffractometry. It is shown that this technique is a powerful tool to observe structural changes during reaction. It offers also a valuable access to thermodynamic and kinetic data for solid state and gas phase reactions. (NH₄)₂SnF₆ decomposes under ammonia below room temperature to NH₄F and amorphous SnF₄ · x NH₃. At a temperature of 80°C an intermediate product, (NH₄)₄SnF₈, is formed, which decomposes at 140°C into (NH₄)₂SnF₆ and NH₄F. At 250°C (NH₄)[Sn(NH₃)F₅] and Sn(NH₃)₂F₄ are formed. The latter crystallises C-centered monoclinic with lattice constants a = 844.1(5) pm, b = 630.5(3) pm, c = 520.2(3) pm and b? = 114.02(7)°. At 330°C a further decomposition yields SnF₂(NH₂)₂ with a C-centered monoclinic cell and lattice constants a = 1 069(7), b = 325.3(2), c = 504.8(3) pm and b? = 105.83(7)°. Finally above 500°C tin metal is formed.     

Synthese und Kristallstruktur von LiHSO4

Synthesis and Crystal Structure of LiHSO₄ Single crystals of the new compound LiHSO₄ are synthezised from the system Lithiumsulfate/Sulfuric acid. The up to day not determined structure of the title compound is monoclinic, space group P2₁/c with the lattice constants a = 5.234(2), b = 7.322(1) and c = 8.363(1) Å, b? = 90.02(2)°. The volume of the unit cell has been determined to V = 320.5 ų, the number of formula units to Z = 4 and the density to D_x = 2.156 g cm^?3. There are crystallographically identical SO₃(OH)- and LiO₄-tetrahedra in the structure. Every tetraheda is linked to four different tetrahedra of the other sort. Two neighboured LiO4 terahedra form a common edge. In that way layers are formed running parallel the yz-plane. These layers are connected over hydrogen bonds.     

Synthese und Struktur von (Ph3PAu)3Mn(CO)4

Synthesis and Structure of (Ph₃PAu)₃Mn(CO)₄ Photolysis of (Ph₃PAu)Mn(CO)₅, Ph₃PAuN₃ and Ph₃PAuNCO yields (Ph₃PAu)₃Mn(CO)₄ ( 1 ). 1 crystallizes in the monoclinic space group P2₁/n with a = 1 031.3(1); b = 3 095.2(3), c = 3 386.3(3) pm; β = 97.58(3)°; Z = 8. The crystal structure contains two symmetry independent clusters 1 of the same geometry. Their inner core MnAu₃ forms a rhombus with distances Mn? Au of about the same lengths between 258.4(4) and 262.0(4) pm. The distances Au? Au range from 276.6(2) to 281.3(2) pm. The bonding in 1 is discussed and compared with those of (Ph₃PAu)₃Co(CO)₃ having the same total number of electrons but a tetrahedral framework.     

Synthese und Kristallstruktur von Mangan(II)‐ und Zinkamid,Mn(NH2)2 und Zn(NH2)2

Synthesis and Crystal Structure of Manganese(II) and Zinc Amides, Mn(NH₂)₂ and Zn(NH₂)₂ Metal powders of manganese resp. zinc react with supercritical ammonia in autoclaves in the presence of a mineralizer Na₂Mn(NH₂)₄ resp. Na₂Zn(NH₂)₄_.0.5NH₃ to well crystallized ruby‐red Mn(NH₂)₂ (p(NH₃) = 100 bar, T = 130°C, 10 d) resp. colourless Zn(NH₂)₂ (p(NH₃) = 3.8 kbar, T = 250°C, 60 d). The structures including all H‐positions were solved by x‐ray single crystal data: Mn(NH₂)₂: I4₁/acd, Z = 32, a = 10.185(6) Å, c = 20.349(7) Å, N(F_o) with F > 3σ (F) = 313, N(parameter) = 45, R/R_w = 0.038/0.043. Zn(NH₂)₂: I4₁/acd, Z = 32, a = 9.973(3) Å, c = 19.644(5) Å, N(F_o) with F > 3σ (F) = 489, N(parameter) = 45, R/R_w = 0.038/0.043. Both compounds crystallize isotypic with Mg(NH₂)₂ [1] resp. Be(NH₂)₂ [2]. Nitrogen of the amide ions is distorted cubic close packed. One quarter of tetrahedral voids is occupied by Mn²⁺‐ resp. Zn²⁺‐ions in such an ordered way that units M₄(NH₂)₆(NH₂)_4/2 occur. The H‐atoms of the anions have such an orientation that the distance to neighboured cations is optimum.     

Yb3+,Er3+掺杂的NaGd(MoO4)2纳米晶的制备及发光性能

采用水热合成技术成功制备了一种新型的上转换发光纳米晶体NaGd(MoO4)2:Yb3+,Er3+.采用X射线粉末衍射分析、透射电镜和光谱分析对不同条件下所得样品的结构和发光性能进行了表征.NaGd(MoO4)2:Yb3+,Er3+和NaGd(MoO4)2具有相同的晶体结构,属于四方晶系;透射电镜观察表明,所得晶体为直径约为20 nm的纳米棒;在980 nm红外激光器的激发下,观察到了3个明显的上转换发射峰,发光中心分别位于531,552和656 nm,分别对应于Er3+2H11/2→I15/2,4S3/2→I15/2和4F9/2→4I15/2的跃迁.     

Synthese und Kristallstruktur von CsAu(SO4)2

Synthesis and Crystal Structure of CsAu(SO₄)₂ Light yellow single crystals of CsAu(SO₄)₂ were obtained upon evaporation of a solution of Au(OH)₃ and Cs₂SO₄ in sulfuric acid (96 % H₂SO₄). In the crystal structure (monoclinic, P2₁/c, Z = 4, a = 1029.7(2), b = 893.4(2), c = 901.0(1) pm, β = 111.08(1)°) Au³⁺ is in square planar coordination of oxygen atoms which belong to four SO₄^— ions. According to [Au(SO₄)_4/2]^— puckered layers are formed which are connected by the Cs⁺ ions. The latter are surrounded by five chelating and three monodentate sulfate groups leading to a CN of 13.     

Synthese und Kristallstruktur von K2Mn3S4

Synthesis and Crystal Structure of K₂Mn₃S₄ Single crystals of K₂Mn₃S₄ have been prepared by a fusion reaction of potassium carbonate with manganese in a stream of hydrogen sulfide at 900 °C. K₂Mn₃S₄ crystallizes in a new monoclinic layered structure type (P2/c, a = 7.244(2) Å, b = 5.822(1) Å, c = 11.018(5) Å, β = 112.33(3)°, Z = 2) which can be described as a stacking variant of the orthorhombic Cs₂Mn₃S₄ structure type. Measurements of the magnetic susceptibilities show antiferro‐magnetic interactions.     

Synthese und Kristallstruktur von Bi2ErO4I

Synthesis and Crystal Structure of Bi₂ErO₄I Bi₂ErO₄I was prepared by solid‐state reaction of stoichiometric mixture of BiOI, Bi₂O₃ and Er₂O₃. Bi₂ErO₄I is a new compound and the first bismuth rare earth oxide iodide. The crystal structure was determined by the Rietveldmethod (P4/mmm, a = 3,8896(6) Å, c = 9,554(2) Å, Z = 1). In this structure [M₃O₄]⁺‐layers are interleaved by single I^–‐layers. Er and Bi atoms of Bi₂ErO₄I are 8‐coordinated. The structure can be derived from the LiBi₃O₄Cl₂‐structure type.     

In situ Untersuchungen der Reaktion von Ammoniummonomolybdat, (NH4)2MoO4, mit Ammoniak: Die Struktur von (NH4)2[Mo3O10]

In situ Investigation of the Reaction of Ammonium Monomolybdate (NH₄)₂MoO₄ with Ammonia: The Structure of (NH₄)₂[Mo₃O₁₀] The reactivity of both polymorphs of (NH₄)₂MoO₄ with ammonia was investigated in a temperature range between 20 and 180 °C. Time and temperature controlled X‐ray powder diffraction as well as thermogravimetrical and differential thermal analysis were used to investigate this reaction.The formation of (NH₄)₂[Mo₃O₁₀] from (NH₄)₂MoO₄ is reversible in a humid and irreversible in a dry NH₃ gas flow. Heating (NH₄)₂MoO₄(mP60) under an atmosphere of humid NH₃ at about 170 °C forms (NH₄)₂[Mo₃O₁₀] and succesively cooling yields the (NH₄)₂MoO₄(mS60) polymorph. (NH₄)₂[Mo₃O₁₀] crystallises isostructural to the potassium compound with space group C2/c (No. 15) and lattice constants a = 1398.2(4), b = 804.1(2), b = 921.0(3) pm and β = 98.833(4)°.     

红色荧光粉KYyEu1-y(WO4)x(MoO4)2-x的制备及其发光性能研究

采用高温固相法结合超声波技术合成了红色荧光粉KYyEu1-y(WO4)x(MoO4)2-x系列,探讨了其合成工艺条件,确定了最佳烧结温度为750℃,烧结时间为5 h;并确定了当x=0.5,y=0.1时样品的相对发光亮度达到最大值为118.2,发射峰的位置处在615nm附近(Eu3+离子的5Do→7F2跃迁),色纯度高,显色性能好.经过研究发现,随着钨酸盐的浓度增加,以466 nm波长激发时,Eu3+的5Do→7F2跃迁发射强度也相应增加,当Mo/W=3时亮度达到最大值.     

Synthese,Struktur und Phasenumwandlung von Se4(MoOCl4)2

Synthesis, Crystal Structure, and Phase Transition of Se₄(MoOCl₄)₂ Dark green, very air sensitive crystals of Se₄(MoOCl₄)₂ are formed from selenium and MoOCl₄ at 190°C in a sealed, evacuated glass ampoule in quantitative yield. The structure is built of nearly square planar Se₄²⁺ ions and centrosymmetric dimeric MoOCl₄^? ions which are linked by bridging Cl atoms. At ?21°C Se₄(MoOCl₄)₂ undergoes a reversible solid state phase transition of first order. Structure determinations at ?70°C and 23°C show that during the phase transition the structures of the ions remain unchanged, while the orientations of the ions with respect to each other change in such a way that in the low temperature form the Se₄²⁺ ions obtain a higher coordination number by Cl and O atoms of neighboring MoOCl₄^? ions.     

(NH4)2MoS4引导CdTe QDs自组装及光学性质调控和细胞成像

报道了一种简易、快速调节量子点荧光波长的方法.以GSH为配体水热法合成了发射波长为540 nm左右的绿色荧光CdTe量子点,通过（NH₄）₂MoS₄在加热和常温条件下引导CdTe量子点进行自组装.加热条件下,15 min内可以使发射波长迅速的红移100 nm以上.常温条件下,在48 h内可以缓慢的引导CdTe量子点进行自组装,发射波长缓慢红移70 nm以上.利用对比实验验证了（NH₄）₂MoS₄中的MoS₄^2-对引导CdTe量子点自组装具有特异性,并且构建了一个合理的自组装体的结构单元模型.在细胞成像领域,该自组装体具有潜在的应用前景.     

Rubidium-decaamidodichromat(III), Rb4Cr2(NH2)10 – Synthese und Kristallstruktur

Rubidium Decaamidodichromate(III), Rb₄Cr₂(NH₂)₁₀ – Synthesis and Crystal Structure The reaction of chromium(III) with rubidium amide in a molar ratio of Cr(NH₂)₃/RbNH₂ = 1 : 1.75 at 140 °C and p(NH₃) = 3 kbar in a high-pressure autoclave results after 90 days in dark violet crystals of Rb₄Cr₂(NH₂)₁₀. Structure determination was done by single crystal X-ray methods:Pna2₁ (No. 33), Z = 4, a = 12.244(3) Å, b = 6.727(1) Å, c = 19.775(5) Å, N(F²_o > 3σ(F²_o)) = 1046, N(Var.) = 94, R/R_w = 0,051/0,059&#TAB;The structure of Rb₄Cr₂(NH₂)₁₀ contains isolated, face-sharing N-octahedra around two Cr³⁺-ions giving [Cr(NH₂)₃(NH₂)_3/2]₂^3–. These are arranged to oneanother following the motif of a hexagonal closest packing. They are connected via Rb⁺- and one further amide ion not bound to Cr³⁺. The compound is characterized by thermoanalytical and IR-/Raman-spectroscopic measurements.