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1.
The perseleno‐selenoborates Rb2B2Se7 and Cs3B3Se10 were prepared from the metal selenides, amorphous boron and selenium, the thallium perseleno‐selenoborates Tl2B2Se7 and Tl3B3Se10 directly from the elements in evacuated carbon coated silica tubes by solid state reactions at temperatures between 920 K and 950 K. All structures were refined from single crystal X‐ray diffraction data. The isotypic perseleno‐selenoborates Rb2B2Se7 and Tl2B2Se7 crystallize in the monoclinic space group I 2/a (No. 15) with lattice parameters a = 12.414(3) Å, b = 7.314(2) Å, c = 14.092(3) Å, β = 107.30(3)°, and Z = 4 for Rb2B2Se7 and a = 11.878(2) Å, b = 7.091(2) Å, c = 13.998(3) Å, β = 108.37(3)° with Z = 4 for Tl2B2Se7. The isotypic perseleno‐selenoborates Cs3B3Se10 and Tl3B3Se10 crystallize in the triclinic space group P1 (Cs3B3Se10: a = 7.583(2) Å, b = 8.464(2) Å, c = 15.276(3) Å, α = 107.03(3)°, β = 89.29(3)°, γ = 101.19(3)°, Z = 2, (non‐conventional setting); Tl3B3Se10: a = 7.099(2) Å, b = 8.072(2) Å, c = 14.545(3) Å, α = 105.24(3)°, β = 95.82(3)°, γ = 92.79(3)°, and Z = 2). All crystal structures contain polymeric anionic chains of composition ([B2Se7]2–)n or ([B3Se10]3–)n formed by spirocyclically fused non‐planar five‐membered B2Se3 rings and six‐membered B2Se4 rings in a molar ratio of 1 : 1 or 2 : 1, respectively. All boron atoms have tetrahedral coordination with corner‐sharing BSe4 tetrahedra additionally connected via Se–Se bridges. The cations are situated between three polymeric anionic chains leading to a nine‐fold coordination of the rubidium and thallium cations by selenium in M2B2Se7 (M = Rb, Tl). Coordination numbers of Cs+ (Tl+) in Cs3B3Se10 (Tl3B3Se10) are 12(11) and 11(9).  相似文献   

2.
Systematic studies on selenoborates containing a B12 cluster entity and alkali metal cations led to the new crystalline phase Na6[B18Se17] which consists of a icosahedral B12 cluster completely saturated with trigonal‐planar BSe3 units and sodium counter‐ions. Neighbouring cluster entities are connected in one direction via exocyclic selenium atoms forming the infinite chain anion ([B18Se16Se2/2]6–). The new chalcogenoborate was prepared in a solid state reaction from sodium selenide, amorphous boron and selenium in evacuated carbon coated silica tubes at a temperature of 850 °C. Na6[B18Se17] crystallizes in the monoclinic space group C2/c (no. 15) with a = 18.005(4) Å, b = 16.549(3) Å, c = 11.245(2) Å, β = 91.35(3)° and Z = 4.  相似文献   

3.
Li5B7S13 and Li9B19S33: Two Lithium Thioborates with Novel Highly Polymeric Anion Networks Li5B7S13 (C2/c; a = 17.304(2) Å, b = 21.922(3) Å, c = 12.233(2) Å, β = 134.91(1)°; Z = 8) and Li9B19S33 (C2/c; a = 23.669(9) Å, b = 14.361(3) Å, c = 12.237(3) Å, β = 103.77(2)°; Z = 4) were prepared by reaction of stoichiometric amounts of lithium sulfide, boron, and sulfur at 750°C (Li5B7S13) and 700°C (Li9B19S33) with subsequent annealing. The crystal structures consist of interpenetrating, polymeric boron sulfur anion networks which are formed by corner-sharing of B4S10 and B10S20 units (Li5B7S13), or B19S36 units (Li9B19S33). The lithium cations are situated in between with a strong disorder in Li9B19S33.  相似文献   

4.
Systematic investigations of ternary barium selenoborates led to the new compounds BaB2Se6 and Ba2B4Se13 which represent the first alkaline earth perselenoborates. Appropriate amounts of barium selenide, boron and selenium were filled into carbon coated silica tubes which were sealed under vacuum. The high temperature reactions and subsequent annealing processes were performed in horizontal one‐zone furnaces. By means of single crystal X‐ray diffraction the structure of BaB2Se6 was determined to be orthorhombic, space group Cmca (no. 64) with a = 11.326(2)Å, b = 7.659(2)Å and c = 10.315(2)Å, while for Ba2B4Se13 the monoclinic space group P21/c (no. 14) was found with a = 12.790(3)Å, b = 11.560(2)Å, c = 12.862(3)Å and β = 103.22(3)°. BaB2Se6 exhibits infinite layers of [B2Se62—]‐anions oriented parallel to the a‐b‐plane. Each layer consists of B2Se2four‐membered rings, which are connected via four diselenide bridges. Thus, B6Se12‐rings are formed in which the barium cations are located. Likewise, in Ba2B4Se13 polymeric [B4Se134—]‐anions are running parallel to the a‐c‐plane resulting in a new layered structure type built of alternating B2Se4‐ and B2Se3‐rings which are connected by perseleno contacts.  相似文献   

5.
Li6+2x[B10Se18]Sex (x ≈ 2), an Ion‐conducting Double Salt Li6+2x[B10Se18]Sex (x ≈ 2) was prepared in a solid state reaction from lithium selenide, amorphous boron and selenium in evacuated carbon coated silica tubes at a temperature of 800 °C. Subsequent cooling from 600 °C to 300 °C gave amber colored crystals with the following lattice parameters: space group I2/a (at 173 K); a = 17.411(1) Å, b = 21.900(1) Å, c = 17.820(1) Å, β = 101.6(1)°. The crystal structure contains a well‐defined polymeric selenoborate network of composition ([B10Se16Se4/2]6?)n consisting of a system of edge‐sharing [B10Se16Se4/2] adamantanoid macro‐tetrahedra forming large channels in which a strongly disorderd system of partial occupied Li+ cations and additional disordered Se2? anions is observed. The crystal structure of the novel selenoborate is isotypic to Li6+2x[B10S18]Sx (x ≈ 2) [1]. X‐ray and 7Li magic‐angle spinning NMR data suggest that the site occupancies of the three crystallographically distinct lithium ions exhibit a significant temperature dependence. The lithium ion mobility has been characterized by detailed temperature dependent NMR lineshape and spin‐lattice relaxation measurements.  相似文献   

6.
The new compounds K2Au2Ge2S6 ( 1 ), K2Au2Sn2Se6 ( 2 ), and Cs2Au2SnS4 ( 3 ) have been synthesized through direct reaction of the elements with a molten polyalkalithiogermanate(stannate) flux at 650, 550, and 400 °C, respectively. Their crystal structures have been determined by single crystal X-ray diffraction techniques. 1 crystallizes in the monoclinic space group P21/n with a = 10.633(2) Å, b = 11.127(2) Å, c = 11.303(2) Å, β = 115,37(3)°, V = 1208,2(3) Å3 and Z = 4, final R(Rw) = 0.045(0.106). 2 crystallizes in the tetragonal space group P4/mcc with a = 8.251(1) Å, c = 19.961(4) Å, V = 1358,9(4) Å3 and Z = 4, final R(Rw) = 0.040(0.076). 3 crystallizes in the orthorhombic space group Fddd with a = 6.143(1) Å, b = 14.296(3) Å, c = 24.578(5) Å, V = 2158.4(7) Å3 and Z = 4, final R(Rw) = 0.039(0.095). The structures of 1 , 2 , and 3 consist of infinite, one-dimensional anionic chains containing X2Q64– units linked by Au+ ions and charge balancing K+/Cs+ ions situated between the chains. All compounds were investigated with differential thermal analysis, FT-IR, and solid state UV/VIS diffuse reflectance spectroscopy.  相似文献   

7.
Cs2B2S4 – A Derivative of the Dimeric Metathioboric Acid Cs2B2S4 (structure: I41/acd; a = 7.270(1) Å, c = 35.737(7) Å; Z = 8; substructure: I4/mmm; a′ = 5.141(1) Å, c′ = 17.868(4) Å, Z = 2) is prepared by the reaction of cesium sulfide with stoichiometric amounts of boron and sulfur (effective molar ratio M:B:S = 2:2:4) at 600°C and subsequent annealing. The crystal structure contains isolated [B2S4]2? groups consisting of four-membered B2S2 rings with two exocyclic sulfur atoms on each of the boron atoms. The cesium cations are nine-coordinate between these rings. The structural feature of two edge-sharing BS3 groups forming an isolated anion appears for the first time in thioborate chemistry, although it is known as a part of the polymeric network in B2S3.  相似文献   

8.
New Alkali Metal Chromium Chalcogenides and their Structural Classification The compounds RbCr3S5, K3Cr11S18, RbCr5Se8 and CsCr5Se8 could be obtained in the form of wellshaped crystals via fusion reactions of the alkali metal carbonates with chromium and the corresponding chalcogen. The compounds crystallize in the monoclinic space groups C2/m (RbCr3S5: a = 19.372(3) Å, b = 3.498(1) Å, c = 12.119(2) Å, β = 122.78(1)°, Z = 4; K3Cr11S18: a = 41.876(3) Å, b = 3.463(1) Å, c = 16.315(3) Å, β = 150.07(1)°, Z = 2; RbCr5Se8: a = 18.737(2) Å, b = 3.623(1) Å; c = 9.016(1) Å, β = 104.65(1)°, Z = 2; CsCr5Se8: a = 18.795(2) Å, b = 3.637(1) Å, c = 9.104(1) Å, β = 104.52(1)°, Z = 2). We propose a structure classification from group-subgroup-relations. MAPLE calculations reveal that the reactions of the binary chalcogenides to yield the ternary compounds are exothermic in each case and are dependent on the chromium/alkali metal ratio in the ternary chalcogenides.  相似文献   

9.
For the first time perthioborates with trigonal planar coordination of boron were prepared. Na2B2S5 (Pnma, a = 12.545(2) Å, b = 7.441(1) Å, c = 8.271(1) Å, Z = 4) and Li2B2S5 (Cmcm, a = 15.864(1) Å, b = 6.433(1) Å, c = 6.862(1) Å, Z = 4) were obtained by reaction of the metal sulfides with stoichiometric amounts of boron and an excess of sulfur (effective molar ratio M:B:S = 1:1:4) at 600°C (650°C) and subsequent annealing. The non-isotypic structures contain exactly planar [B2S5]2? groups consisting of five-membered B2S3 rings with one additional exocyclic sulfur on each of the boron atoms. The alkaline metal cations are four-coordinate (lithium) and (four + four)-coordinate (sodium) respectively.  相似文献   

10.
Two new ternary compounds with composition K8Zr6Se30 were prepared by reacting zirconium powder in potassium polyselenide melts. Both compounds crystallize in the triclinic space group P1 with a = 12.391(1) Å, b = 14.897(2) Å, c = 15.253(2) Å, α = 73.149(9)°, β = 76.330(9)°, γ = 70.023(9)° and V = 2502.8(3) Å3 for I and a = 12.2793(8) Å, b = 14.887(1) Å, c = 22.512(2) Å, α = 72.714(7)°, β = 88.475(7)°, γ = 70.748(7)° and V = 3698.1(4) Å3 for II . Their structures consist of infinite linear one‐dimensional anionic chains running parallel to [110], which are connected by the potassium cations. The structural differences between both compounds originate from some disordering in one of the two crystallographically independent anionic chains of each compound, in which Se2– anions are exchanged by Se22– anions to some degree. The optical band gap was determined by UV/Vis reflectance spectra to 1.91 eV for I and 1.81 eV for II . Differential scanning calorimetry investigations show, that II decomposes reversibly at about 500 °C to K2Se3 and ZrSe3. On cooling II is formed again. These results are confirmed by the direct reaction between K2Se3 and ZrSe3 which leads directly to II .  相似文献   

11.
Crystal Structures of the Polyselenides [Cs(18-Crown-6)]2Se5 · DMF, [Rb(222-Crypt)]2Se6, [Ba(15-Crown-5)2]Se6 · DMF, and [Na(12-Crown-4)2]Se7 . The title compounds have been prepared by reactions of the corresponding diselenides with excess selenium in the presence of crown ethers in dimethylformamide solutions, forming black crystals. [Cs(18-Crown-6)]2Se5 · DMF: Space group P21/m, Z = 2, 2 194 observed unique reflections, R = 0.119. Lattice dimensions at 20°C: a = 1 041.2; b = 1 496.3; c = 1 459.7 pm; β = 100.39°. The compound forms an ionic triple with Cs…Se-contacts between 374 and 381 pm. [Rb(222-Crypt)]2Se6: Space group P1 , Z = 2, 7 405 observed unique reflections, R = 0.056. Lattice dimensions at – 70°C: a = 1 106.8; b = 1 460.8; c = 1 718.8 pm; α = 89.22°; β = 86.65°; γ = 71.53°. The compound contains Se62? chains without direct contact with each other. [Ba(15-Crown-5)2]Se6 · DMF: Space group P21/n, Z = 4, 2 680 observed unique reflections, R = 0.055. Lattice dimensions at – 80°C: a = 1 051.9; b = 1 322.4; c = 2 729.9 pm; β = 100.93°. The compound contains Se62? chains, which are isolated from each other by the cations and the included DMF molecules. [Na(12-Crown-4)2]2Se7: Space group P1 , Z = 2, 7 313 observed unique reflections, R = 0.042. Lattice dimensions at – 70°C: a = 1 260.9; b = 1 433.6; c = 1 462.9 pm; α = 80.27°; β = 78.60°; γ = 69.34°. The compound contains Se72? chains without direct contacts with each other.  相似文献   

12.
LiBaBS3 and LiBaB3S6: Two New Quaternary Thioborates with Trigonally Coordinated Boron LiBaBS3 (P21/c; a = 7.577(2) Å, b = 8.713(2) Å, c = 8.687(2) Å, β = 116.22(2)°; Z = 4) und LiBaB3S6 (Cc; a = 15.116(3) Å, b = 8.824(2) Å, c = 8.179(2) Å, β = 117.46(3)°; Z = 4) were prepared by reaction of stoichiometric amounts of the metal sulfides, boron, and sulfur at 750°C. The anionic part of the structure of the orthothioborate LiBaBS3 consists of isolated planar [BS3]3? anions. The crystal structure of the metathioborate LiBaB3S6 contains [B3S6]3? anions formed by six-membered B3S3 rings with three exocyclic sulfur atoms. The metal cations are situated between the anion units leading to a ninefold sulfur coordination of the barium atoms and to a fivefold (LiBaBS3) and fourfold (LiBaB3S6) coordination of the lithium atoms.  相似文献   

13.
The tetraphosphorus tetraselenide P4Se4 is prepared and described for the first time. It is synthetised easily by heating between 250°C and 300°C a mixture of selenide P4Se3 and selenium. It exists under two allotropie forms, α P4Se4 transforming in β P4Se4 at 300°C. α P4Se4 cristallises in the orthorhombie system (a = 7.199 Å; b = 8.661 Å; c = 12.619 Å) as β P4Se4 (a = 9.3200 Å; b = 16.8601 Å; c = 14.3399 Å). The results of the mass spectrometry and the infra-red spectrometry suggest that the structure of the new compound derives from the tetrahedral structure of white phosphorus.  相似文献   

14.
The new compounds K6Nb4S22 and K6Ta4S22 ( I ) have been synthesised by the reaction of NbS2 or Ta metal in a K2S3 flux. Using TaS2 as educt a second modification of K6Ta4S22 ( II ) is obtained. K6Nb4S22 and K6Ta4S22 (form I ) crystallise in the monoclinic space group C2/c with a = 35.634 (2)Å, b = 7.8448 (4)Å, c = 12.1505 (5)Å, β = 100.853 (5)°, V = 3335.8 (3)Å3, and Z = 4 for K6Nb4S22 and a = 35.563 (7) Å, b = 7.836 (2)Å, c = 12.139 (2)Å, β = 100.56 (3)°, V = 3325.5 (2)Å3, and Z = 4 for K6Ta4S22 ( I ). The second modification K6Ta4S22 (form II ) crystallises in the monoclinic space group P21/c with a = 7.5835 (6)Å, b = 8.7115 (5)Å, c = 24.421 (2)Å, β = 98.733 (9)°, V = 1594.6 (2)Å3, and Z = 2. The structures consist of [M4S22]6— anions composed of two M2S11 sub‐units which are linked into M4S22 units via terminal sulfur ligands. The anions are well separated by the K+ cations. Differences between the structures of the title compounds and those with the heavier alkali cations Rb+ and Cs+ are caused by the different arrangement of the [M4S22]6— anions around the cations and the different S2—/S22— binding modes. The thermal behaviour of both modifications was investigated using differential scanning calorimetry (DSC). From these investigations there is no hint for a polymorphic transition between the two forms. After heating crystals of form II above the melting point and cooling the melt to room temperature a crystalline powder of form I can be isolated.  相似文献   

15.
Chalcogenohalogenogallates(III) and -indates(III): A New Class of Compounds for Elements of the Third Main Group. Preparation and Structure of [Ph4P]2[In2SX6], [Et4N]3[In3E3Cl6] · MeCN and [Et4N]3[Ga3S3Cl6] · THF (X = Cl, Br; E = S, Se) [In2SCl6]2?, [In2SBr6]2?, [In3S3Cl6]3?, [In3Se3Cl6]3?, and [Ga3S3Cl6]3? were synthesised as the first known chalcogenohalogeno anions of main group 3 elements. [Ph4P]2[In2SCl6] ( 1 ) (P1 ; a = 10.876(4) Å, b = 12.711(6) Å, c = 19.634(7) Å, α = 107.21(3)°, β = 96.80(3)°, γ = 109.78(3)°; Z = 2) and [Ph4P]2[In2SBr6] ( 2 ) (C2/c; a = 48.290(9) Å, b = 11.974(4) Å, c = 17.188(5) Å, β = 93.57(3)°, Z = 8) were prepared by reaction of InX3, (CH3)3SiSSi(CH3)3 and Ph4PX (X = Cl, Br) in acetonitrile. The reaction of MCl3 (M = Ga, In) with Et4NSH/Et4NSeH in acetonitrile gave [Et4N]3[In3S3Cl6] · MeCN ( 3 ) (P21/c; a = 17.328(4) Å, b = 12.694(3) Å, c = 21.409(4) Å, β = 112.18(1)°, Z = 4), [Et4N]3[In3Se3Cl6] · MeCN ( 4 ) (P21/c; a = 17.460(4) Å, b = 12.816(2) Å, c = 21.513(4) Å, β = 112.16(2)°, Z = 4), and [Et4N]3[Ga3S3Cl6] · THF ( 5 ) (P21/n; a = 11.967(3) Å, b = 23.404(9) Å, c = 16.260(3) Å, β = 90.75(2)°, Z = 4). The [In2SX6]2? anions (X = Cl, Br) in 1 and 2 consist of two InSX3 tetrahedra sharing a common sulfur atom. The frameworks of 3, 4 and 5 each contain a six-membered ring of alternating metal and chalcogen atoms. Two terminal chlorine atoms complete a distorted tetrahedral coordination sphere around each metal atom.  相似文献   

16.
The crystal structures of SiPb2S4 and SiPb2Se4 were determined from three dimensional X-ray diffraction data collected with Mo radiation. Both structures are monoclinic with space group P21c and 4 formula units per unit cell. Lattice dimensions for SiPb2S4 are a = 6.4721(5) Å, b = 6.6344(9) Å, c = 16.832(1) Å, and β = 108.805(7)°. For SiPb2Se4, a = 8.5670(2) Å, b = 7.0745(3) Å, c = 13.6160(3) Å, and β = 108.355(3)°. The Si is tetrahedrally coordinated to S and Se with SiS about 2.10 Å and SiSe about 2.27 Å. The structural framework can be described as consisting of trigonal prisms of S or Se atoms which form a prismatic tube by sharing the triangular faces. These tubes in turn share edges to form corrugated sheets, with the unshared edges projecting alternately on each side of the sheet. The structures are very similar but not identical. In the sulfide one Pb is in sevenfold coordination and the other crystallographically independent Pb is in eightfold coordination. The PbS distances range from 2.82–3.50 Å. In SiPb2Se4 both Pb atoms are in sevenfold coordination. PbSe distances range from 2.97 to 3.54 Å. In the sulfide the Pb atoms form a zig-zag chain within the channels formed by the prismatic tubes while in the selenide they are in a straight line.  相似文献   

17.
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   

18.
Sr3(BS3)2 and Sr3(B3S6)2: Two Novel Non‐oxidic Chalcogenoborates with Boron in a Trigonal‐Planar Coordination The thioborates Sr3(BS3)2 and Sr3(B3S6)2 were prepared from strontium sulfide, amorphous boron and sulfur in solid state reactions at a temperature of 1123 K. In a systematic study on the structural cation influence on this type of ternary compounds, the crystal structures were determined by single crystal X‐ray diffraction. Sr3(BS3)2 crystallizes in the monoclinic spacegroup C2/c (No. 15) with a = 10.187(4) Å, b = 6.610(2) Å, c = 15.411(7) Å, β = 102.24(3)° and Z = 4. The crystal structure of Sr3(B3S6)2 is trigonal, spacegroup R3¯ (Nr. 148), with a = 8.605(1) Å, c = 21.542(4) Å and Z = 3. Sr3(BS3)2 contains isolated [BS3]3— anions with boron in a trigonal‐planar coordination. The strontium cations are found between the layers of orthothioborate anions. Sr3(B3S6)2 consists of cyclic [B3S6]3— anions and strontium cations, respectively.  相似文献   

19.
Selenostannates from Aqueous Solution, Preparation and Structure of Na4Sn2Se6 · 13 H2O The dimeric anion Sn2Se64? is prepared by reaction of SnSe2 with alkali metal selenide in a 1:1 molar ratio. The orange-red hydrated sodium salt Na4Sn2Se6 · 13 H2O is characterized by a complete X-ray structure analysis and by its vibrational spectrum. The compound is triclinic (P1 ) with a = 7.106(2), b = 10.330(2), c = 19.009(4) Å, α = 78.60(2), β = 85.66(2), γ = 72.85(2)° (?130°C), Z = 2. It contains isolated Sn2Se64? anions consisting of two edge-sharing tetrahedra [Sn? Se 2.456(1)–2.589(1) Å] which are in contact to the hydrated Na+ ions within an extensive hydrogen bridge system. Raman-active vibrations are observed at 260, 202, 188, 116, 93, and 78 cm?1.  相似文献   

20.
The Crystal Structure of K2S3 and K2Se3 Well formed crystals of K2S3 and K2Se3 were obtained by reaction of the elements in liquid ammonia at 500 bar and 150°C. The substances are both orthorhombic, space group Cmc21. Cell constants are: The structure contains S32?(Se32?) polyanions, with S? S? S(Se? Se? Se) angles of 105.4(102.5)°. The S? S(Se? Se) distance is 2.083(2.383) Å.  相似文献   

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