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1.
Synthesis and Crystal Structures of [P(C6H5)4][1-(NH3)B10H9] and Cs[(NH3)B12H11] · 2CH3OH The reduction of [1-(NO2)B10H9]2? with aluminum in alkaline solution yields [1-(NH3)B10H9]? and by treatment of [B12H12]2? with hydroxylamine-O-sulfonic acid [(NH3)B12H11]? is formed. The crystal structures of [P(C6H5)4][1-(NH3)B10H9] (triclinic, space group P1 , a = 7.491(2), b = 13.341(2), c = 14.235(1) Å, α = 68.127(9), β = 81.85(2), γ = 86.860(3)°, Z = 2) and Cs[(NH3)B12H11] · 2CH3OH (monoclinic, space group P21/n, a = 14.570(2), b = 7.796(1), c = 15.076(2) Å, β = 111.801(8)°, Z = 4) reveal for both compounds the bonding of an ammine substituent to the cluster anion.  相似文献   

2.
Through extensive research on the PbO / PbBr2 / B2O3 system, a new single crystal of yellow lead‐containing oxyborate bromine, [O2Pb3]2(BO3)Br, was grown from the melt. It crystallizes in the centrosymmetric space group Cmcm (no. 63) of the orthorhombic system with the following unit cell dimensions: a = 9.5748(8) Å, b = 20.841(2) Å, c = 5.7696(5) Å, and Z = 4. The whole structure is characterized by an infinite one‐dimensional (1D) 1[O2Pb3] double chain, which is based on the OPb4 oxocentered tetrahedra and considered as the derivative of the continuous sheet of OPb4 tetrahedra from the tetragonal modification of α‐PbO. The 1D 1[O2Pb3] double chains are further bridged by the BO3 units through common oxygen atoms to form two‐dimensional (2D) 1[[(O2Pb3)(BO3)] layers, with Br atoms situated between the layers. IR spectroscopy, UV/Vis/NIR diffuse reflectance spectroscopy, and thermal analysis were also performed on the reported material.  相似文献   

3.
Two new barium borate bromide crystals, Ba2BO3Br and Ba3BO3Br3, have been obtained by spontaneous crystallization. Ba2BO3Br crystallizes in P−3m1 space group, with cell parameters of a = 5.5157(10) Å, c = 11.019(4) Å, and Z = 2, its structure is build up by alternately stacking along c-axis of [Ba2(BO3)2]2− layers and bromide [Ba2Br2]2+ layers. The solved structure is analog to Ba2(BO3)1−x(CO3)xCl1+x except the interstitial halogen atoms at (0, 0, 1/2) is missing and accordingly the partly CO3 substitution for BO3 has not been observed. Ba3BO3Br3 crystallizes in a new structure type with P−1 space group and cell parameters of a = 9.280(4) Å, b = 9.349(7) Å, c = 13.025(9) Å, α = 92.71(3)°, β = 98.29(3)°, γ = 116.200(18)° and Z = 4. The basic structural unit in Ba3BO3Br3 is the clusters composed of 4 BO3 groups and 12 Ba atoms, which in turn are linked by eight Ba–O bonds with other four clusters to form sheets extend in the (001) plane.  相似文献   

4.
Pale pink crystals of Nd2(SeO3)2(SeO4) · 2H2O were synthesized under hydrothermal conditions from H2SeO3 and Nd2O3 at about 200 °C. X‐ray diffraction on powder and single‐crystals revealed that the compound crystallizes with the monoclinic space group C 2/c (a = 12.276(1) Å, b = 7.0783(5) Å, c = 13.329(1) Å, β = 104.276(7)°). The crystal structure of Nd2(SeO3)2(SeO4) · 2H2O is an ordered variant of the corresponding erbium compound. Eight oxygen atoms coordinate the NdIII atom in the shape of a bi‐capped trigonal prism. The oxygen atoms are part of pyramidal (SeIVO3)2? groups, (SeVIO4)2? tetrahedra and water molecules. The [NdO8] polyhedra share edges to form chains oriented along [010]. The selenate ions link these chains into layers parallel to (001). The layers are interconnected by the selenite ions into a three‐dimensional framework. The dehydration of Nd2(SeO3)2(SeO4) · 2H2O starts at 260 °C. The thermal decomposition into Nd2SeO5, SeO2 and O2 at 680 °C is followed by further loss of SeO2 leaving cubic Nd2O3.  相似文献   

5.
The new quaternary thiogermanates, ATaGeS5 (A = K, Rb, Cs) were prepared with the use of halide fluxes and the crystal structures of the compounds were determined by single‐crystal X‐ray diffraction methods. The compounds are isostructural and crystallize in space group P\bar{1} of the triclinic system with two formula units in a cell of dimensions: a = 6.937(1) Å, b = 6.950(2) Å, c = 8.844(3) Å, α = 71.07(2)°, β = 78.56(2)°, γ = 75.75(2)°, V = 387.6(2) Å3 for KTaGeS5; a = 6.996(3) Å, b = 7.033(3) Å, c = 8.985(4) Å, α = 70.33(3)°, β = 78.12(4)°, γ = 75.63(4)°, V = 399.6(3) Å3 for RbTaGeS5; a = 7.012(4) Å, b = 7.202(3) Å, c = 9.267(5) Å, α = 68.55(3)°, β = 77.27(4)°, γ = 74.75(4)°, V = 416.2(4) Å3 for CsTaGeS5. The structures of ATaGeS5 (A = K, Rb, Cs) are comprised of anionic infinite two‐dimensional {}_\infty^2 [TaGeS5] layers separated from one another by alkali metal cations (A+). Each layer is made up of tantalum centered sulfur octahedra and pairs of edge‐sharing germanium centered sulfur tetrahedra. The classical charge valence of these compounds should be represented by [A+][(Ta5+)(Ge4+)(S2–)5]. UV/Vis diffuse reflectance measurements indicate that they are semiconductors with optical bandgaps of ca. 2.0 eV.  相似文献   

6.
Crystal of a new neodymium oxyborate fluoride Nd6Li(BO3)3O4F2 was grown by the flux method. Its structure, determined by single crystal x-ray diffraction, belongs to the space group C2/c with cell parameters of a = 12.0629(2) Å, b = 6.94650(10) Å, c = 16.0528(3) Å, β = 104.5360(10)°. In the structure, Nd atoms coordinate to oxygen or fluorine atoms to yeild 7 or 8 coordinated Nd(O,F)n polyhedra. Those polyhedra are edge-shared to form a double layer of (Nd12O23F4)14? fluorite blocks. The blocks are linked by oxygen atoms of planar BO3 groups in the c direction into a 3-dimensional network. Another novel element in the structure is that Li coordinates to 6 oxygen atoms from three BO3 groups forming a propeller like arrangement, and theoretical calculation shows that such arrangement should give 3/4 that of BO3 contribution to second harmonic effect. The crystal shows deep violet color with typical Nd3+ optical absorption and a UV transmission cut-off of 260 nm.  相似文献   

7.
Two new rare earth containing orthoborate crystals ASr4La3(BO3)6 (A = Li, Na) have been obtained by spontaneous nucleation from high-temperature melts of A2O–SrO–La2O3–B2O3–AF. X-ray diffraction analyses show that they both crystallize in the rhombohedral space group R-3 with cell parameters of a = 12.309(7) Å, c = 9.316(7) Å and a = 12.4049(13) Å, c = 9.348(2) Å for the Li and Na compounds respectively. Similar to the large A′6MM′(BO3)6 family, these compounds are all related to the structure of Sr3Y(BO3)3 with La and Sr statistically occupy the Sr site, and the alkaline elements and remaining Sr enter the ordered Y1 and Y2 sites, which can be approximately represented as (La2.91Sr3.09)(La0.09Sr0.91)Li[B6O18] and (La2.85Sr3.15)(La0.15Sr0.85)Na[B6O18]. The characteristic of the structure is that the La/Sr and isolated BO3 groups form a network with tunnels along the c-axis where the alkaline A and Sr ions alternatively reside. The optical transmission spectrum shows that the ultraviolet absorption edge of NaSr4La3(BO3)6 crystal is about 193 nm and Raman spectra reveal that both crystals possess sharp peaks at 930 cm−1.  相似文献   

8.
The magnesium borate fluoride Mg5(BO3)3F was grown by spontaneous crystallization with molten flux based on the MgF2‐LiF‐Na2CO3‐H3BO3 solvent. Structure solution from single‐crystal X‐ray diffraction shows that the title compound crystallizes in the orthorhombic space group Pnma (No. 62) with cell dimensions of a = 10.068(5) Å, b = 14.858(7) Å, c = 4.540(2) Å and Z = 4. Its structure features a three‐dimensional (3D) Mg‐O‐F framework composed of MgO5F and MgO6 polyhedra and isolated BO3 groups. The detailed structure comparison referred to Mg5(BO3)3F, Mg3BO3F3 and β‐Mg2BO3F was carried out. The infrared spectrum (IR) and the bond valence sum (BVS) calculations of Mg5(BO3)3F verify the validity of the structure. The calculated band structure and the density of states of Mg5(BO3)3F suggest that its indirect bandgap is 5.27 eV. The compound was additionally investigated by UV/Vis‐NIR diffuse reflectance spectroscopy and thermal analysis.  相似文献   

9.
The new compounds A2ZnP2Se6 (A = K, Rb, Cs) were synthesized via molten salt flux syntheses. The crystals feature one‐dimensional 1/[ZnP2Se6]2– chains charge balanced by alkali metal ions between the chains. K2ZnP2Se6 crystallizes in the monoclinic space group P21/c; cell parameters a = 12.537(3) Å, b = 7.2742(14) Å, c = 14.164(3) Å, β = 109.63(3)°, Z = 4, and V = 1216.7(4) Å3. Rb2ZnP2Se6 and Cs2ZnP2Se6 are isotypic, crystallizing in the triclinic space group P$\bar{1}$ . Rb2ZnP2Se6 has cell parameters of a = 7.4944(15) Å, b = 7.6013(15) Å, c = 12.729(3) Å, α = 96.57(3)°, β = 105.52(3)°, γ = 110.54(3)°, Z = 2, and V = 636.6(2) Å3. Cs2ZnP2Se6 has cell parameters of a = 7.6543(6) Å, b = 7.7006(6) Å, c = 12.7373(11) Å, α = 97.007(7)°, β = 104.335(7)°, γ = 109.241(6)°, Z = 2, and V = 669.54(10) Å3.  相似文献   

10.
The reaction of alkali carbonates and selenium acid yielded the “pyroanions” [Se2O7]2– containing alkali diselenates. By varying the alkali carbonates we were able to synthesize and determinate the crystal structures of the whole row from Li to Cs. Li2Se2O7 crystallizes isotypic to Li2S2O7 [Pnma, Z = 4, a = 13.815(3), b = 8.452(2) c = 5.0585(10) Å]. The structure of Na2Se2O7 [P$\bar{1}$ , Z = 2, a = 6.9896(14), b = 6.9938(14), c = 7.0829(14) Å, α = 83.32(3), β = 64.56(3), γ = 83.18(3)°] is isotypic to Ag2S2O7. A2Se2O7 (A = K, Rb) [A = K: C2/c, Z = 4, a = 12.851(3), b = 7.5677(15), c = 7.5677(15) Å, β = 93.35(3)°; A = Rb: C2/c, Z = 4, a = 13.118(3), b = 7.7963(16), c = 7.7811(16) Å, β = 94.03(3)°] are isotypic to K2S2O7. The crystal structure of Cs2Se2O7 [P$\bar{1}$ , Z = 10, a = 7.7271(3), b = 16.2408(8), c = 18.4427(8) Å, α = 89.685(2), β = 89.193(2), γ = 76.251(2)°] seems to be isotypic to the averaged room‐temperature modification of Cs2S2O7. With exception of the caesium compound all diselenate anions show an ecliptic arrangement and can be therefore classified as dichromate‐like structures. In Cs2Se2O7 most of the [Se2O7]2– units have a staggered alignment. The transition between both orientations can be explained by the increase of the cations size. Additionally the vibrational spectra of A2Se2O7 with A = Li – Cs are discussed as well as the resulting bond forces.  相似文献   

11.
A novel beryllium borate CsBe4(BO3)3 has been grown in crystals by high-temperature flux method using spontaneous nucleation technique for the first time. The crystal structure of this compound was determined by single crystal X-ray diffraction analysis. It crystallizes in the orthorhombic space group Pnma with lattice parameters a = 8.3914(5) Å, b = 13.3674(7) Å, c = 6.4391(3) Å, Z = 4, V = 722.28(7) Å3. The crystal takes the same structure type as Rb analog based on the units of BO3 triangles and BeO4 tetrahedrons, displaying a three-dimensional tunnel structure with Cs atoms filling in the cages. The IR spectrum confirms the presence of BO3 groups and the UV–vis–IR diffuse reflectance spectrum exhibits this compound has a short UV cut-off edge below 200 nm. Band structures and density of states were calculated.  相似文献   

12.
Cs[Na(NH3)6][B10H10]·NH3 was synthesised from cesium and disodium‐decahydro‐closo‐decaborate Na2B10H10 in liquid ammonia, from which it crystallized in form of temperature sensitive colorless plates (triclinic, P1¯, a = 8.4787(7) Å, b = 13.272(1) Å, c = 17.139(2) Å, α = 88.564(1)°, β = 89.773(1)°, γ = 81.630(1)°, V = 1907.5(3) Å3, Z = 4). The compound is the first example of an alkali metal boranate with two different types of cations. The decahydro‐closo‐decaborate dianions [B10H10]2— and the cesium cations form a equation/tex2gif-stack-1.gif[Cs2(B10H10)2]2— layer parallel to the ac plane. These layers are separated by N—H···N‐hydrogen bonded hexamminesodium cations.  相似文献   

13.
A series of MVO(SO4)2 vanadium complexes, where M = Rb, Cs, or Tl, were prepared, and their crystal structures and physicochemical properties studied. The rubidium and thallium compounds of this series were found to be isostructural to each other and to crystallize, like KVO(SO4)2 and NH4VO(SO4)2, in orthorhombic system (space group P212121, No. 19, Z = 4) with the unit cell parameters a = 4.9735(2) Å, b=8.7894(4) Å, c = 16.6968(8) Å, V = 729.88 Å3 (Rb); and a = 4.9636(1) Å, b = 8.7399(2) Å, c = 16.8598(4) Å, V = 731.39 Å3 (Tl). The cesium compound was found to crystallize in monoclinic system (space group P21/a, No. 14-2, Z = 4): a = 10.0968(6) Å, b = 8.9131(4) Å, c = 9.8675(5) Å, β = 114.640(2)°, V = 807.16 Å3. The MVO(SO4)2 crystal structure is built of VO6 octahedra, which are linked into layers by bridging SO4 groups. At the apex of each VO6 octahedron, there is a short V-O terminal bond having a length of 1.54(1) Å (Rb), 1.57(2) Å (Tl), and 1.52(4) Å (Cs).  相似文献   

14.
Conformation and Cross Linking of (CuCN)6‐Rings in Polymeric Cyanocuprates(I) equation/tex2gif-stack-8.gif [Cu2(CN)3] (n = 2, 3) The alkaline‐tricyano‐dicuprates(I) Rbequation/tex2gif-stack-9.gif[Cu2(CN)3] · H2O ( 1 ) and Csequation/tex2gif-stack-10.gif[Cu2(CN)3] · H2O ( 2 ) were synthesized by hydrothermal reaction of CuCN and RbCN or CsCN. The dialkylammonium‐tricyano‐dicuprates(I) [NH2(Me)2]equation/tex2gif-stack-11.gif[Cu2(CN)3] ( 3 ), [NH2(iPr)2]equation/tex2gif-stack-12.gif[Cu2(CN)3] ( 4 ), [NH2(Pr)2]equation/tex2gif-stack-13.gif[Cu2(CN)3] ( 5 ) and [NH2(secBu)2]equation/tex2gif-stack-14.gif[Cu2(CN)3] ( 6 ) were obtained by the reaction of dimethylamine, diisopropylamine, dipropylamine or di‐sec‐butylamine with CuCN and NaCN in the presence of formic acid. The crystal structures of these compounds are built up by (CuCN)6‐rings with varying conformations, which are connected to layers ( 1 ) or three‐dimensional zeolite type cyanocuprate(I) frameworks, depending on the size and shape of the cations ( 2 to 6 ). Crystal structure data: 1 , monoclinic, P21/c, a = 12.021(3)Å, b = 8.396(2)Å, c = 7.483(2)Å, β = 95.853(5)°, V = 751.4(3)Å3, Z = 4, dc = 2.728 gcm—1, R1 = 0.036; 2 , orthorhombic, Pbca, a = 8.760(2)Å, b = 6.781(2)Å, c = 27.113(5)Å, V = 1610.5(5)Å3, Z = 8, dc = 2.937 gcm—1, R1 = 0.028; 3 , orthorhombic, Pna21, a = 13.504(3)Å, b = 7.445(2)Å, c = 8.206(2)Å, V = 825.0(3)Å3, Z = 4, dc = 2.023 gcm—1, R1 = 0.022; 4 , orthorhombic, Pbca, a = 12.848(6)Å, b = 13.370(7)Å, c = 13.967(7)Å, V = 2399(2)Å3, Z = 8, dc = 1.702 gcm—1, R1 = 0.022; 5 , monoclinic, P21/n, a = 8.079(3)Å, b = 14.550(5)Å, c = 11.012(4)Å, β = 99.282(8)°, V = 1277.6(8)Å3, Z = 4, dc = 1.598 gcm—1, R1 = 0.039; 6 , monoclinic, P21/c, a = 16.215(4)Å, b = 13.977(4)Å, c = 14.176(4)Å, β = 114.555(5)°, V = 2922(2)Å3, Z = 8, dc = 1.525 gcm—1, R1 = 0.070.  相似文献   

15.
Pr(BO2)3 and PrCl(BO2)2: Two Praseodymium meta‐Borates in Comparison Single‐crystalline PrCl(BO2)2 can be obtained by the reaction of praseodymium, Pr6O11 and PrCl3 with a small excess of B2O3 in evacuated silica tubes after seven days at 850 °C. If NaCl is additionally used as flux, single crystals of Pr(BO2)3 dominate the main product. Both praseodymium(III) meta‐borates are air and water stable. The crystals of PrCl(BO2)2 emerge as long, thin, pale green needles which tend to severe twinning due to their fibrous habit. The crystal structure (triclinic, P1¯; a = 420.56(4), b = 655.42(7), c = 808.34(8) pm, α = 82.361(8), β = 89.173(9), γ = 71.980(7)°, Z = 2) exhibits zigzag chains {[(B1)ot1/1Oe2/2(B2)Ot1/1Oe2/2]2−} (≡ {[BO2]}) of corner‐linked [BO3]3− triangles with syndiotactic orientation of the terminal oxygen atoms which are running parallel to the [100] direction. The Pr3+ cations are surrounded by three Cl and seven O2− anions with the shape of a tetracapped trigonal prism. The green, transparent crystals of Pr(BO2)3 (monoclinic, C2/c; a= 984.98(9), b = 809.57(8), c = 641.02(6) pm, β = 126.783(9)°, Z = 4) appear either lath‐shaped or rather spherical. In the crystal structure the B3+ cations reside both in trigonal planar as well as in tetrahedral coordination of oxygen atoms. Both types of borate polyhedra ([BO3]3− and [BO4]5−) are linked via corners to form chains of the composition {[(B2)‐Ot1/1Oe2/2(B1)Oe4/2(B2)Ot1/1Oe2/2]3−} (≡ {[BO2]}) which run parallel [101]. The coordination sphere of the Pr3+ cations consists of ten oxide anions which build up a bicapped square antiprism.  相似文献   

16.
Er5(BO3)2F9 was synthesised under conditions of 3 GPa and 800 °C in a Walker‐type multianvil apparatus. The crystal structure was determined on the basis of single‐crystal X‐ray diffraction data, collected at room temperature. Er5(BO3)2F9 is isotypic to the recently synthesised Yb5(BO3)2F9 and crystallises in C2/c with the lattice parameters a = 2031.2(4) pm, b = 609.5(2) pm, c = 824.6(2) pm, and β = 100.29(3)°. The physical properties of RE5(BO3)2F9 (RE = Er, Yb) including high temperature behaviour and single crystal IR‐ / Raman spectroscopy were investigated.  相似文献   

17.
Diammine cobalt(II) chloride, Co(N(H, D)3)2Cl2 was prepared by decomposition of the corresponding hexaammines at 120 °C in dynamical vacuum. Crystal structures and magnetic properties of these materials were characterised by X‐ray and neutron powder diffraction, and heat capacity measurements. At ambient temperatures Co(N(H, D)3)2Cl2 crystallises in the Cd(NH3)2Cl2 type structure: space group Cmmm, Z = 2, a = 8.0512(2) Å, b = 8.0525(2) Å, c = 3.73318(9) Å (X‐ray data of the H compound). This structure consists of chains of edge‐sharing octahedra [CoCl4/2(NH3)2] running along the c‐axis. Neutron diffraction confirms that that the ND3 groups are rotationally disordered at ambient temperatures. At 1.5 K and 20 K neutron diffraction data reveal rotational ordering of the ND3 groups leading to doubling of the c‐axis and to Ibmm symmetry: a = 7.9999(6) Å, b = 7.9911(5) Å, c = 7.4033(3) Å (Z = 4, values for T = 1.5 K). Furthermore, antiferromagnetic ordering is present at these temperatures. It is caused by a ferromagnetic coupling of the magnetic moments at Co2+ (3.60(5) μB at 1.5 K, 3.22(5) μB at 20 K) along the octahedra chains [CoCl4/2(NH3)2] and antiferromagnetic coupling between neighbouring chains. According to heat capacity measurements the phase transition antiferromagnetic‐paramagnetic takes place at TN = 26 K.  相似文献   

18.
RbLi2Ga2(BO3)3     
The structure of rubidium dilithium digallium tris­(borate), RbLi2Ga2(BO3)3, contains two‐dimensional sheets of open‐branched rings of GaO4 tetrahedra and planar BO3 triangles that are joined by LiO4 tetrahedra to form a three‐dimensional framework. Ten‐coordinate Rb atoms lie on twofold axes and occupy channels within the framework that extend along the b axis.  相似文献   

19.
The new octadecanuclear Cu‐Ln complex, [Cu12Nd6(OH)24(betaine)16(NO3)3(H2O)10](NO3)[PF6]14·5H2O, was synthesized, which crystallizes in triclinic P1¯ space group, a = 18.649(6)Å, b = 20.363(7)Å, c = 19.865(7)Å, α = 116.61(2)°, β = 91.99(2)°, γ = 117.93(2)°, V = 5666(3)Å3. Its crystal structure features a [Cu12Nd6(OH)24(betaine)16(NO3)3(H2O)10]15+ core of pseudocubic Oh symmetry, with the six Nd ions positioned at the vertices of a regular octahedron and the twelve Cu ions located at the midpoints of the twelve octahedral edges. The Cu‐Nd metal framework may be viewed as a cuboctahedron, which is interconnected by twenty‐four μ3‐OH bridges that are each linked to one Nd ion and two Cu ions. In the centre of metal polyhedron, there is an encapsulated NO3 anion that exhibits a multi‐ coordinating mode.  相似文献   

20.
Preparation and Properties of the Alkali Hexaiodatogermanates(IV), M2[Ge(IO3)6] Germanium dioxide aquate and alkali nitrates react with iodic acid to yield alkali hexaiodatogermanates(IV), M2[Ge(IO3)6], (M = NH4, K, Rb, Cs). The unit-cell dimensions of the trigonal cell are for K2[Ge(JO3)6] a0 = 11.16 Å, c0 = 11.34 Å, z = 3. The compounds M[MIV(IO3)6] (MI = NH4, K, Rb, Cs, MIV = Ge, Sn, Pb, Ti, Zr, Mn) are isomorphous1).  相似文献   

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