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1.
Bulk assemblies of zero-dimensional (0D) metal halides with ‘host-guest’ system provide a promising platform for rationally structural tunability and photoluminescence modulation. In this work, we first report a series of ternary 0D metal halides, (bmpy)9[Pb3Cl11](MnCl4)2-2x(SbCl5)2x (bmpy+ = 1-buty-1-methylpyrrolidinium+, C9NH20+), where the organic cation bmpy+ cocrystallizes with [Pb3Cl11]5- trimer clusters, [MnCl4]2? tetrahedra, and [SbCl5]2? pyramids. The emission color of (bmpy)9[Pb3Cl11](MnCl4)2-2x(SbCl5)2x can be easily tuned from green to warm white and finally to orange-red by controlling the excitation wavelength or the [SbCl5]2?/[MnCl4]2? molar ratio, promising its potential for application in multicolor light-emitting devices or even in encrypting multilevel optical codes. This work presents a novel structural modulation strategy to fabricate superior ordered single-crystalline multicomponent materials with multifunctionalities of 0D luminescent metal halides.  相似文献   

2.
Lead‐free zero‐dimensional (0D) organic‐inorganic metal halide perovskites have recently attracted increasing attention for their excellent photoluminescence properties and chemical stability. Here, we report the synthesis and characterization of an air‐stable 0D mixed metal halide perovskite (C8NH12)4Bi0.57Sb0.43Br7?H2O, in which individual [BiBr6]3? and [SbBr6]3? octahedral units are completely isolated and surrounded by the large organic cation C8H12N+. Upon photoexcitation, the bulk crystals exhibit ultra‐broadband emission ranging from 400 to 850 nm, which originates from both free excitons and self‐trapped excitons. This is the first example of 0D perovskites with broadband emission spanning the entire visible spectrum. In addition, (C8NH12)4Bi0.57Sb0.43Br7?H2O exhibits excellent humidity and light stability. These findings present a new direction towards the design of environmentally‐friendly, high‐performance 0D perovskite light emitters.  相似文献   

3.
Lead‐free zero‐dimensional (0D) organic‐inorganic metal halide perovskites have recently attracted increasing attention for their excellent photoluminescence properties and chemical stability. Here, we report the synthesis and characterization of an air‐stable 0D mixed metal halide perovskite (C8NH12)4Bi0.57Sb0.43Br7?H2O, in which individual [BiBr6]3? and [SbBr6]3? octahedral units are completely isolated and surrounded by the large organic cation C8H12N+. Upon photoexcitation, the bulk crystals exhibit ultra‐broadband emission ranging from 400 to 850 nm, which originates from both free excitons and self‐trapped excitons. This is the first example of 0D perovskites with broadband emission spanning the entire visible spectrum. In addition, (C8NH12)4Bi0.57Sb0.43Br7?H2O exhibits excellent humidity and light stability. These findings present a new direction towards the design of environmentally‐friendly, high‐performance 0D perovskite light emitters.  相似文献   

4.
Bromoplumbates with One‐dimensional Polymeric and Isolated Anions: (Bzl4P)2[Pb3Br8], (Bzl4P)2[Pb3Br8(dmf)2], (Bzl4P)[PbBr3], (Bzl4P)2[PbBr4], and (Bzl4P)4[Pb2Br6][PbBr4] PbBr2 reacts with LiBr and (Bzl4P)(PF6) (Bzl = CH2C6H5) in acetone to form a series of bromoplumbate complexes with compositions and structures depending on the conditions of reaction and crystallization. While the anions in (Bzl4P)2[Pb3Br8] ( 1 ) and (Bzl4P)[PbBr3] ( 2 ) are one‐dimensional polymers with penta‐ and hexacoordinated Pb atoms, the metal atoms in the mono‐ and dinuclear complex anions of (Bzl4P)2[PbBr4] · 2acetone ( 3 · 2acetone) and (Bzl4P)4[Pb2Br6][PbBr4] ( 4 ) bind to four bromo ligands. From DMF as a solvent (Bzl4P)2[Pb3Br8(dmf)2] ( 1 b ) crystallizes with the same bromoplumbate structure as in 1 a , but with dmf ligands occupying the coordination sites vacant in 1 a . Upon radiation of compound 3 with ultraviolet light greenish yellow photoluminescence (emssion maximum at 547 nm) is observed. Crystallographic details see “Inhaltsübersicht”.  相似文献   

5.
An Octahedral Niobium Cluster containing Six Terminal Azide Groups: The Structure of Rb4[Nb6Br12(N3)6](H2O)2 Six terminal halide ligands of [Nb6Br12Br6]4? can be substituted in solution by azide ions. Single-crystals of Rb4[Nb6Br12(N3)6](H2O)2 were obtained during the evaporation of the water/methanol solvent, and structurally characterized by X-ray methods: Space group P21/c, Z = 2, a = 970.8(5) pm, b = 1525.4(7) pm, c = 1280.0(7) pm, β = 97.15(6)°. The [Nb6Br12(N3)6]4? ions contain six terminal azide groups at the corners of the octahedral niobium cluster (d Nb–N = 227 pm). The [Nb6Br12(N3)6]4? ions are interconnected by Rb+ and H2O. Crystals of Rb4[Nb6Br12(N3)6](H2O)2 are explosive towards heat or mechanic pressure.  相似文献   

6.
Synthesis and Crystal Structure Determination of Lead(II) Oxide Halide Alcoholates with Different Connectivity of Pb4O4 Heterocubane‐like Subunits The reaction of red lead(II) oxide (Litharge) and lead(II) halide (Cl? and Br?) with diethylene glycole at a temperature of 180 °C leads to the isotypic compounds [Pb6(C4H8O3)O2Cl6] (1) and [Pb6(C4H8O3)O2Br6] (2) . In a similar synthesis with PbI2 as educt at temperature of 160 °C the two modifications β‐[Pb6(C4H8O3)O2I6] (3) and α‐[Pb6(C4H8O3)O2I6] (4) were found, whereas at a reaction temperature of 180 °C [Pb9(C2H4O2)(C4H8O3)O3I8] (5) was surprisingly obtained as product. The X‐ray diffraction data show that at a temperature of 180 °C a splitting of the ether took place. The cited compounds show cubane like subunits built by lead and oxygen atoms. These fragments are connected by alkoholate molecules. In 5 additionally an I6 octahedra centered by lead is observed.  相似文献   

7.
Synthesis, Structure and Thermolysis of NH4[Re3Br10] NH4[Re3Br10] crystallizes as dark brown single crystals upon slow cooling of a hot, saturated hydrobromic-acid solution of [Re3Br9(H2O)2] after the addition of NH4Br. The crystal structure (monoclinic, C2/m (Nr. 12); Z = 4; a = 1461.6(7), b = 1 085.6(4), c = 1030.3(7) pm, β = 92.63(4)°, Vm = 245.9(4)cm3/mol; R = 0.097, Rw = 0.043) contains [Re3Br12]? units that share two common edges. These chains run along [010] and are held together by NH4+ ions. Each NH4+ is surrounded by eight Br? from four different chains. The first step of the thermal decomposition at 290°C is the disproportionation to ReBr3 (ReCl3 type), rhenium metal and (NH4)2[ReBr6]. Secondly, the internal reduction of (NH4)2[ReBr6] at 390°C to rhenium metal takes place.  相似文献   

8.
Considering the instability and low photoluminescence quantum yield (PLQY) of blue‐emitting perovskites, it is still challenging and attractive to construct single crystalline hybrid lead halides with highly stable and efficient blue light emission. Herein, by rationally introducing d10 transition metal into single lead halide as new structural building unit and optical emitting center, we prepared a bimetallic halide of [(NH4)2]CuPbBr5 with new type of three‐dimensional (3D) anionic framework. [(NH4)2]CuPbBr5 exhibits strong band‐edge blue emission (441 nm) with a high PLQY of 32 % upon excitation with UV light. Detailed photophysical studies indicate [(NH4)2]CuPbBr5 also displays broadband red light emissions derived from self‐trapped states. Furthermore, the 3D framework features high structural and optical stabilities at extreme environments during at least three years. To our best knowledge, this work represents the first 3D non‐perovskite bimetallic halide with highly efficient and stable blue light emission.  相似文献   

9.
A nest-shaped cluster [(C4H9)4N]2[WOSe3Cu3Br1.67Cl1.33] (1) and a cage-shaped cluster [(C4H9)4N]3[WSe4Cu3Br2Cl2] (2) were synthesized and their structures were determined by single-crystal X-ray diffraction. It was found that cluster 1 showed better optical limiting properties under an 8 ns pulsed laser at 532 nm but poorer optical limiting properties under a 35 ps pulsed laser compared with its analogue [(C4H9)4N]2[MoOS3Cu3BrCl2]. The influence of the peripheral ligands of the cluster to the optical limiting properties was also discussed.  相似文献   

10.
The bromine‐rich bromidoplatinates(IV) [NBu3Me]2[Pt2Br10](Br2)2 ( 1 ) and [NBu3Me]2[Pt2Br10](Br2)3 ( 2 ) were prepared by reaction of PtBr4 and elemental bromine in the ionic liquid [MeBu3N][N(Tf)2] [N(Tf)2 = bis(trifluoromethylsulfonyl)amide]. Both bromine‐rich bromidoplatinates(IV) contain [Pt2Br10]2– anions and [NBu3Me]+ cations as voluminous building units with an almost identical structural arrangement and very similar unit cells. The difference of the title compounds is related to the specific number of Br2 molecules that link the [Pt2Br10]2– anions to three‐dimensional networks. Whereas 1 is relatively stable under inert conditions, 2 releases bromine even at ambient pressure. The title compounds are characterized by single‐crystal structure analysis and Raman spectroscopy.  相似文献   

11.
Ammonium chloride and bromide, (NH4)Cl and (NH4)Br, act on elemental iron producing divalent iron in [Fe(NH3)2]Cl2 and [Fe(NH3)2]Br2, respectively, as single crystals at temperatures around 450 °C. Iron(III) chloride and bromide, FeCl3 and FeBr3, react with (NH4)Cl and (NH4)Br producing the erythrosiderites (NH4)2[Fe(NH3)Cl5] and (NH4)2[Fe(NH3)Br5], respectively, at fairly low temperatures (350 °C). At higher temperatures, 400 °C, iron(III) in (NH4)2[Fe(NH3)Cl5] is reduced to iron(II) forming (NH4)FeCl3 and, further, [Fe(NH3)2]Cl2 in an ammonia atmosphere. The reaction (NH4)Br + Fe (4:1) leads at 500 °C to the unexpected hitherto unknown [Fe(NH3)6]3[Fe8Br14], a mixed‐valent FeII/FeI compound. Thermal analysis under ammonia and the conditions of DTA/TG and powder X‐ray diffractometry shows that, for example, FeCl2 reacts with ammonia yielding in a strongly exothermic reaction [Fe(NH3)6]Cl2 that at higher temperatures produces [Fe(NH3)]Cl2, FeCl2 and, finally, Fe3N.  相似文献   

12.
Inhaltsübersicht. Die beiden silicathaltigen Blei(II)-oxidhalogenide Pb4[SiO4]Cl4 und Pb4[SiO4]Br4 wurden erstmals dargestellt und ihre Kristallstruktur an Einkristallen mit Röntgen-beugungsmethoden ermittelt. Die Verbindungen kristallisieren in der monoklinen Raumgruppe P21/c (No. 14) mit den Gitterparametern: Pb4[SiO4]Cl4: A = 8,73(1) Å, b = 15,68(1) Å, c = 8,265(6) Å, β = 92,4(1)°, Z = 4 Pb4[SiO4]Br4: A = 9,00(1) Å, b = 16,217(8) Å, c = 8,404(4) Å, β = 92,4(1)°, Z = 4 Im Gegensatz zu der “nichtstöchiometrischen” Verbindungsgruppe um Pb8O7Br2 · SiO2 konnten hier alle Atomlagen ermittelt werden. Es liegen einzelne SiO4-Gruppen vor, die über Pb2+ zu leicht gewellten Netzen verbunden sind. Zwischenräume und Löcher der Netze werden von Halogenidionen aufgefüllt. Preparation and Crystal Structures of the First Two Members of a New Type of Lead (II) Oxyhalides, Pb4[SiO4]X4 (X = Cl, Br) Both silicate-bearing lead(II) oxyhalides Pb4[SiO4]Cl4 and Pb4[SiO4]Br4 were prepared and studied for their crystal structure with X-ray single crystal methods for the first time. The compounds crystallize in the monoclinic space group P21/c (No. 14) with following lattice parameters: Pb4[SiO4]Cl4: A = 8.73(1) Å, b = 15.68(1) Å, c = 8.205(6) Å, β = 92.4(1)°, Z = 4 Pb4[SiO4]Br4: A = 9.00(1) Å, b = 16.217(8) Å, c = 8.404(4) Å, β = 92.4(1)°, Z = 4. In contrast with further works about the group of nonstoichiometric lead oxyhalides Pb8O7Br2 · SiO2 in the present work all atomic positions were determined. The crystal structure shows single SiO4 groups linked only by Pb2+ ions to form slightly undulated nets. Holes and interspaces of these nets are stuffed with halide ions.  相似文献   

13.
To gain more insight into the reactivity of intermetalloid clusters, the reactivity of the Zintl phase K12Sn17, which contains [Sn4]4? and [Sn9]4? cluster anions, was investigated. The reaction of K12Sn17 with gold(I) phosphine chloride yielded K7[(η2‐Sn4)Au(η2‐Sn4)](NH3)16 ( 1 ) and K17[(η2‐Sn4)Au(η2‐Sn4)]2(NH2)3(NH3)52 ( 2 ), which both contain the anion [(Sn4)Au(Sn4)]7? ( 1 a ) that consists of two [Sn4]4? tetrahedra linked through a central gold atom. Anion 1 a represents the first binary Au?Sn polyanion. From this reaction, the solvate structure [K([2.2.2]crypt)]3K[Sn9](NH3)18 ( 3 ; [2.2.2]crypt=4,7,13,16,21,24‐hexaoxa‐1,10‐diazabicyclo[8.8.8]hexacosane) was also obtained. In the analogous reaction of mesitylcopper with K12Sn17 in the presence of [18]crown‐6 in liquid ammonia, crystals of the composition [K([18]crown‐6)]2[K([18]crown‐6)(MesH)(NH3)][Cu@Sn9](thf) ( 4 ) were isolated ([18]crown‐6=1,4,7,10,13,16‐hexaoxacyclooctadiene, MesH=mesitylene, thf=tetrahydrofuran) and featured a [Cu@Sn9]3? cluster. A similar reaction with [2.2.2]crypt as a sequestering agent led to the formation of crystals of [K[2.2.2]crypt][MesCuMes] ( 5 ). The cocrystallization of mesitylene in 4 and the presence of [MesCuMes]? ( 5 a ) in 5 provides strong evidence that the migration of a bare Cu atom into an Sn9 anion takes place through the release of a Mes? anion from mesitylcopper, which either migrates to another mesitylcopper to form 5 a or is subsequently protonated to give MesH.  相似文献   

14.
By means of alternating current electrochemical synthesis crystals of [C13H15N2]+2[CuCl2.58Br1.42] ( I ) and [C13H15N2]+[Cu2Cl0.67Br2.33] ( II ) have been obtained and structurally characterized. Compound I crystallizes in the orthorhombic system, space group Fddd, a = 7.828(1) Å, b = 26.402(2) Å, c = 28.595(3) Å, Dc = 1.4995(5) g/cm3, Z = 8, R = 0.067 for 2157 reflections. The CuX42– tetrahedra are connected with the organic cations through an electrostatic interaction. Crystals of II are monoclinic, space group P21/c, a = 9.2293(8) Å, b = 22.1332(9) Å, c = 9.2939(9) Å, β = 118.021(4)°, Dc = 2.1251(5) g/cm3, Z = 4, R = 0.042 for 2858 reflections. A tetrahedral environment of the Cu1 atom involves four halide atoms, whereas Cu2 possesses a trigonal‐pyramidal coordination with the C=C‐bond and three halide atoms.  相似文献   

15.
The novel title compound, [(CH3)4N]2[Ta6Br12(H2O)6]Br4·2H2O, with a [Ta6Br12]2+ cluster unit, has been prepared and structurally characterized. The compound crystallizes in space group C2/c, with a twofold axis passing through the cluster and the centre of symmetry located between the clusters. The nearest neighbouring cluster units are aligned along the crystallographic c axis, forming a one‐dimensional chain pattern.  相似文献   

16.
The compound [NH4(NH3)4][Co(C2B9H11)2] · 2 NH3 ( 1 ) was prepared by the reaction of Na[Co(C2B9H11)2] with a proton‐charged ion‐exchange resin in liquid ammonia. The ammoniate 1 was characterized by low temperature single‐crystal X‐ray structure analysis. The anionic part of the structure consists of [Co(C2B9H11)2] complexes, which are connected via C‐H···H‐B dihydrogen bonds. Furthermore, 1 contains an infinite equation/tex2gif-stack-2.gif[{NH4(NH3)4}+(μ‐NH3)2] cationic chain, which is formed by [NH4(NH3)4]+ ions linked by two ammonia molecules. The N‐H···N hydrogen bonds range from 1.92 to 2.71Å (DHA = Donor···Acceptor angles: 136‐176°). Additional N‐H···H‐B dihydrogen bonds are observed (H···H: 2.3‐2.4Å).  相似文献   

17.
Zero‐dimensional (0D) organic metal halide hybrids, in which organic and metal halide ions cocrystallize to form neutral species, are a promising platform for the development of multifunctional crystalline materials. Herein we report the design, synthesis, and characterization of a ternary 0D organic metal halide hybrid, (HMTA)4PbMn0.69Sn0.31Br8, in which the organic cation N‐benzylhexamethylenetetrammonium (HMTA+, C13H19N4+) cocrystallizes with PbBr42?, MnBr42?, and SnBr42?. The wide band gap of the organic cation and distinct optical characteristics of the three metal bromide anions enabled the single‐crystalline “host–guest” system to exhibit emissions from multiple “guest” metal halide species simultaneously. The combination of these emissions led to near‐perfect white emission with a photoluminescence quantum efficiency of around 73 %. Owing to distinct excitations of the three metal halide species, warm‐ to cool‐white emissions could be generated by controlling the excitation wavelength.  相似文献   

18.
刘泉  徐庆锋  张勇  陈金香  周志峰  郎建平 《中国化学》2002,20(12):1602-1607
IntroductionThechemistryofthethiometallateanionsiscurrentlyasubjectofintenseinterestduetotheirrichstructuraldi versity ,1 8theirrelevancetoindustrialcatalyticprocess9,10andmetalloenzymes ,11,12 andtheirpotentialutilityasnon linearopticalmaterials .13 16Wehaverep…  相似文献   

19.
Crystal Structure of (NMe4)2[Re3Br11(H2O)] [Re3Br9(H2O)3](H2O)2 . (NMe4)2[Re3Br11(H2O)] [Re3Br9(H2O)3](H2O)2 crystallizes from hydrobromic acid solution of Re3Br9 · 2 H2O and NMe4Br at 0 – 5°C. The crystal structure (monoclinic; P21/m (Nr. 11); a = 967.9(3); b = 1 529.7(4); c = 1 710.9(4) pm; β = 91.66(2)°; Z = 2; R = 0.113; Rw = 0.068) has been determined from four-circle diffractometer data. The structure contains two different cluster units of trivalent rhenium, isolated anionic [Re3Br11(H2O)]2? units and neutral cluster units that are connected through crystal water molecules to chains{[Re3Br9(H2O)3](H2O)2}.  相似文献   

20.
Halogenation of nido-B10H14 with C2H2Cl4, C2Cl6, Br2, or I2, produces by cluster degradation the (2 n)-closo-clusters B9X9 (X = Cl, Br, I). The synthesis of salts of the perhalogenated radical anions of the type (2 n + 1)-closo-[B9X9]· – and of the corresponding dianions (2 n + 2)-closo-[B9X9]2– from neutral B9X9 is described [n is the number of cluster atoms; (2 n), (2 n + 1), and (2 n + 2) is the number of cluster electrons]. Molecular and crystal structures of B9Cl9, B9Br9, [(C6H5)4P][B9Br9] · CH2Cl2, and [(C4H9)4N]2[B9Br9] · CH2Cl2 have been determined via X-ray diffraction. All three oxidation states of the cluster retain the tricapped trigonal prism. The reduction of the clusters B9X9 was shown by cyclic voltammetry in CH2Cl2 to proceed via two successive one-electron reversible steps, separated by at least 0.4 V. The paramagnetic radical anions [B9X9]· – (X = Cl, Br) were further characterized by magnetic susceptibility measurements of [Cp2Fe][B9X9] and [Cp2Co][B9X9], respectively. The EPR spectra of [B9X9]· – (X = Cl, Br, I) in glassy frozen CH2Cl2 solutions showed increasing g anisotropy for the heavier halogen derivatives, illustrating significant halogen participation at the singly occupied MO. The 11B NMR spectra of CD2Cl2 solutions of the neutral clusters B9X9 exhibit only one sharp resonance, indicating that the boron atoms are highly fluxional in solution. In contrast, two different boron resonances as expected for a rigid tricapped trigonal prism are clearly observed for the [B9X9]2– dianions in solutions and for solid B9Br9 in the 11B MAS NMR spectra. Temperature dependent 11B MAS NMR experiments on B9Br9 and [B9Br9]2– in the solid state show a reversible coalescence of the two resonances at higher temperature. 11B MAS NMR spectra and DTA measurements of [B9Br9]2– showed a phase transition.  相似文献   

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