- Phase diagram of the Sb-Se-I system and thermodynamic properties of SbSeI
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The Sb-Se-I system was investigated by using the DTA and XRD analyses and EMF measurements with an antimony electrode. The T-x diagram of the binary Sb-I system was accurately redefined. A number of polythermal sections and the projection of the liquidus surface were constructed. The fields of the primary crystallization, as well as the types and coordinates of non- and monovariant equilibria were determined. It is shown that the quasi-binary sections Sb 2Se3-SbI3, Sb-SbSeI, SbI3-Se, and SbSeI-Se triangulate the Sb-Se-I system, leading to five independent subsystems. A broad area of immiscibility, that overlaps a certain part of the antimony primary crystallization field, was found. From the EMF measurements, the partial molar functions of antimony (ΔG?,ΔH?,ΔS?) as well as standard integral thermodynamic functions of SbSeI were calculated. The latter were found to have the following values: ΔGf,2980=-80.121.81kJ/mol; ΔHf,2980=-77.31.8kJ/mol; S2980=155.29.5J/(molK).
- Aliev,Musaeva,Babanly,Shevelkov,Babanly
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- DODECAFLUORO- AND DODECACHLORO-5,10-o-BENZENOSTIBANTHRENE
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Sb2(C6F4)3 and Sb2(C6Cl4)3 can be synthesised simply by heating together 1,2-I2C6X4 (X = F, Cl) and powdered antimony in sealed tubes.Both compounds form hemi-solvates with a variety of organic solvents; typically, the weak hexane solvate of Sb2(C6F4)3 loses hexane slowly at room temperature.The mass spectra, and the 13C NMR spectrum of Sb2(C6F4)3, are described.Chlorine reacts with Sb2(C6F4)3 to give Sb2(C6F4)3Cl4 which, on boiling with water, forms the oxide Sb2(C6F4)3O2.Sb2(C6F4)3 is oxidised by concentrated nitric acid to the dinitrate Sb2(C6F4)3(OH)2(NO3)2 which slowly hydrolyses in aqueous solution to form the tetrahydroxo derivative Sb2(C6F4)3(OH)4.
- Al-Jabar, N.A.A.,Massey, A.G.
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- Direct Gap Semiconductors Pb2BiS2I3, Sn2BiS2I3, and Sn2BiSI5
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New quaternary thioiodides Pb2BiS2I3, Sn2BiS2I3, and Sn2BiSI5 have been synthesized by isothermal heating as well as chemical vapor transport. Pb2BiS2I3 and Sn2BiS2I3 crystallize in the space group, Cmcm, with unit cell parameters a = 4.3214 (9), b = 14.258 (3), and c = 16.488 (3) ? a = 4.2890 (6), b = 14.121(2), and c = 16.414 (3) ?, respectively. Sn2BiSI5 adopts a unique crystal structure that crystallizes in C2/m with cell parameters a = 14.175 (3), b = 4.3985 (9), c = 21.625 (4) ?, and β = 98.90(3)°. The crystal structures of Pb2BiS2I3 and Sn2BiS2I3 are strongly anisotropic and can be described as three-dimensional networks that are composed of parallel infinite ribbons of [M4S2I4] (M = Pb, Sn, Bi) running along the crystallographic c-axis. The crystal structure of Sn2BiSI5 is a homologue of the M2BiS2I3 (M = Pb, Sn) which has two successive ribbons of [M4S2I4] separated by two interstitial (Sn1-xBixI6) octahedral units. These compounds were characterized by scanning electron microscopy, differential thermal analysis, and X-ray photoelectron spectroscopy. Pb2SbS2I3, Pb2BiS2I3, Pb2Sb1-xBixS2I3 (x ～ 0.4), Sn2BiS2I3 and Sn2BiSI5 are highly resistive and exhibit electrical resistivities of 3.0 G cm, 100 M cm, 65 M cm, 1.2 M cm, and 34 M cm, respectively, at room temperature. Pb2BiS2I3, Sn2BiS2I3, Pb2SbS2I3, Pb2Sb1-xBixS2I3 (x ～ 0.4), and Sn2BiSI5 are semiconductors with bandgaps of 1.60, 1.22, 1.92, 1.66, and 1.32 eV, respectively. The electronic band structures of Pb2BiS2I3, Sn2BiS2I3, and Sn2BiSI5, calculated using density functional theory, show that all compounds are direct bandgap semiconductors.
- Islam, Saiful M.,Malliakas, Christos D.,Sarma, Debajit,Maloney, David C.,Stoumpos, Constantinos C.,Kontsevoi, Oleg Y.,Freeman, Arthur J.,Kanatzidis, Mercouri G.
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- Strong Electron-Phonon Coupling and Self-Trapped Excitons in the Defect Halide Perovskites A3M2I9 (A = Cs, Rb; M = Bi, Sb)
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The optical and electronic properties of Bridgman grown single crystals of the wide-bandgap semiconducting defect halide perovskites A3M2I9 (A = Cs, Rb; M = Bi, Sb) have been investigated. Intense Raman scattering was observed at room temperature for each compound, indicating high polarizability and strong electron-phonon coupling. Both low-temperature and room-temperature photoluminescence (PL) were measured for each compound. Cs3Sb2I9 and Rb3Sb2I9 have broad PL emission bands between 1.75 and 2.05 eV with peaks at 1.96 and 1.92 eV, respectively. The Cs3Bi2I9 PL spectra showed broad emission consisting of several overlapping bands in the 1.65-2.2 eV range. Evidence of strong electron-phonon coupling comparable to that of the alkali halides was observed in phonon broadening of the PL emission. Effective phonon energies obtained from temperature-dependent PL measurements were in agreement with the Raman peak energies. A model is proposed whereby electron-phonon interactions in Cs3Sb2I9, Rb3Sb2I9, and Cs3Bi2I9 induce small polarons, resulting in trapping of excitons by the lattice. The recombination of these self-trapped excitons is responsible for the broad PL emission. Rb3Bi2I9, Rb3Sb2I9, and Cs3Bi2I9 exhibit high resistivity and photoconductivity response under laser photoexcitation, indicating that these compounds possess potential as semiconductor hard radiation detector materials.
- McCall, Kyle M.,Stoumpos, Constantinos C.,Kostina, Svetlana S.,Kanatzidis, Mercouri G.,Wessels, Bruce W.
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- A new preparative approach to HgPbP14 structure type materials: Crystal structure of Cu0.73(1)Sn1.27(1)P14 and characterization of M1-xSn1+xP14 (M = Cu, Ag) and AgSbP14
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A new preparative approach, using main group iodides as mineralization agents, was developed to prepare bulk quantities of HgPbP14 [(M1)(M2)P14] type polyphosphides containing group 11 cations on the M1 and main group elements Sn or formerly unseen Sb on the M2 position. The known (M1)2+:(M2)2+ combination of cations is extended with the combination (M1)1+:(M2)3+ in AgSbP14. A single crystal structure determination was performed for Cu 1-xSn1+xP14. Cu0.73(1)Sn 1.27(1)P14 crystallizes orthorhombically, space group Pnma (No. 62) with lattice constants a = 12.513(2) A, b = 9.800(1) A, c = 10.445(1) A, V = 1280.8(3) A3 and Z = 4. Small differences in the cell parameters between the single crystal and powder diffraction experiments of CuSnP14 are probably due to a small homogeneity range. Tetravalent tin postulated beside divalent tin for isostructural Au0.64Sn1.36P14 could not be detected by 119Sn-Moessbauer spectroscopic experiments for the copper tin polyphosphide. An ionic description like [(M1+) 1-x(M24+)]2+ [(M22+)(P 0)10(P1-)4]2- with x = 0.33 according to a Zintl-Klemm concept has to be substituted by a more covalent description of [(M1+)1-x(M22+) x](1+x)+- [(M22+)(P14)] (1+x)- for the copper tin polyphosphide.
- Lange, Stefan,Sebastian, C. Peter,Nilges, Tom
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- Complexes of group 15 metals with sterically hindered thiolate ligands. Crystal and molecular structures of [Sb(2-SC5H4N)3], [Sb(2-SC5H3N-3-SiMe3)3], and [Bi(2-SC5H3N-3-SiMe3)3]
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The complexes [Sb(2-C5H4N)3] (1), [Sb(2-SC5H3N-S-SiMe3)3] (2), and [Bi(2-SC5H3N-3-SiMe3)3] (3) were prepared from the reaction of the appropriate metal salt and the ligand in methanol. The structure of 1 consists of a distorted octahedral arrangement of S and N donors, which adopt a facial ligand arrangement. The stereochemically active lone pair of the Sb(III) center occupies a position capping the N3 face of the octahedron. In contrast, the donor groups in 2 are so disposed that the lone pair occupies an octahedral vertex trans to a sulfur donor, with one nitrogen donor now defining the face capping position. The structure of the bismuth derivative (3) is analogous to that of 2. Crystal data: C15H12N3S3Sb (1); trigonal R3c, a = 12.562 (2) ?, c = 37.960 (4) ?, V = 5187.6 (10) ?3, Z = 12, R = 0.026; C24H36N3Si3S3Sb (2), monoclinic P21/c, a = 17.876 (3) ?, b = 10.772 (2) ?, c = 18.617 (4) ?, β = 116.08 (1)°, V = 3219.8 (11) ?3, Z = 4, R = 0.028; C24H36N3Si3S3Bi (3), monoclinic C2/c, a = 24.682 (4) ?, β = 12.927 (2) ?, c = 24.782 (4) ?, β= 123.04 (1)°, V = 6629.1 (12) ?3, Z = 8, R = 0.049. 1991 American Chemical Society.
- Block, Eric,Ofori-Okai, Gabriel,Kang, Hyunkyu,Wu, Jin,Zubieta, Jon
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p. 4784 - 4788
(2008/10/08)
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- Examination of the reactivity of bis(trifluoromethyl)tellurium: Oxidative trifluoromethylations and ligand exchanges with group 5A and 6A (15 and 16) elements and their halides
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Bis(trifluoromethyl)tellurium reacts with I2, S8, Se, P4, and As at 220°C to afford CF3I, (CF3)2S, (CF3)2Se, (CF3)3P, and (CF3)3As, which are separated in 97, 92, 92, 70, and 46% yields, respectively. The interaction of (CF3)2Te with Sb at 170°C results in very small amounts of (CF3)3Sb, ca. 3%, but no (trifluoromethyl)germanes were observed when (CF3)2Te was exposed to Ge at 170°C. At 170°C the reactions of (CF3)2Te with SeBr4, PI3, and AsI3 generate (CF3)2Se, (CF3)3P, and (CF3)3As, which can be isolated in 98, 65, and 88% yields, respectively. The reaction of SCl2 with (CF3)2Te at 170°C, however, is less productive, presumably because there are several alternative pathways that are competitive with the reaction channel that leads to (CF3)2S. At 170°C SbI3 and (CF3)2Te form trace amounts (ca. 0.2%) of (CF3)3Sb, but in the temperature range 120-170°C, the reaction of GeI4 with (CF3)2Te gave no evidence for the formation of (trifluoromethyl)germanes.
- Ganja,Morrison
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- DODECAFLUORO-5,10-o-BENZENOARSANTHRENE AND DODECAFLUORO-5,10-o-BENZENOSTIBANTHRENE
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To clear some confusion in the literature, the "direct syntheses" of As2(C6F4)3 and of Sb2(C6F4)3 have been repeated and the identities of the compounds confirmed by analytical data and spectroscopic methods.Mixtures of As and Sb, when heated with 1,2-I2C6F4, give As2(C6F4)3, Sb2(C6F4)3 and AsSb(C6F4)3.When Sb is heated with 1,2-I2C6H4 and 1,2-I2C6F4, three compounds are formed: Sb2(C6F4)3, Sb2(C6F4)2(C6H4) and Sb(C6F4)(C6H4)2.
- Mistry, T.K.,Massey, A.G.
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