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Thomas Schleid - One of the best experts on this subject based on the ideXlab platform.
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Sc2[Se2O5]3: The First Rare-Earth Metal Oxoselenate(IV) with Exclusively [Se2O5]2− Anions
Crystals, 2018Co-Authors: Stefan Greiner, Thomas SchleidAbstract:The Scandium oxodiselenate(IV) Sc2[Se2O5]3 was synthesized via solid-state reactions between Scandium sesquioxide (Sc2O3) and selenium dioxide (SeO2) with thallium(I) chloride (TlCl) as fluxing agent in molar ratios of 1:4:2. Evacuated fused silica ampoules were used as reactions vessels for annealing the mixtures for five days at 800 °C. The new Scandium Compound crystallizes in the triclinic space group P 1 ¯ with the lattice parameters a = 663.71(5) pm, b = 1024.32(7) pm, c = 1057.49(8) pm, α = 81.034(2)°, β = 87.468(2)°, γ = 89.237(2)° and Z = 2. There are two distinct Sc3+ positions, which show six-fold coordination by oxygen atoms as [ScO6]9− octahedra (d(Sc–O) = 205–212 pm). Three different [Se2O5]2− anions provide these oxygen atoms with their terminal ligands (Ot). Each of the six selenium(IV) central atoms exhibit a stereochemically active lone pair of electrons, so that all [Se2O5]2− anions consist of two ψ1-tetrahedral [SeO3]2− subunits (d(Se–Ot) = 164–167 pm, d(Se–Ob) = 176–185 pm, ∢(O–Se–O) = 93–104°) sharing one bridging oxygen atom (Ob) with ∢(Se–Ob–Se) = 121–128°. The vibrational modes of the complex anionic [Se2O5]2− entities were characterized via single-crystal Raman spectroscopy.
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Sc2[Se2O5]3: The First Rare-Earth Metal Oxoselenate(IV) with Exclusively [Se2O5]2− Anions
MDPI AG, 2018Co-Authors: Stefan Greiner, Thomas SchleidAbstract:The Scandium oxodiselenate(IV) Sc2[Se2O5]3 was synthesized via solid-state reactions between Scandium sesquioxide (Sc2O3) and selenium dioxide (SeO2) with thallium(I) chloride (TlCl) as fluxing agent in molar ratios of 1:4:2. Evacuated fused silica ampoules were used as reactions vessels for annealing the mixtures for five days at 800 °C. The new Scandium Compound crystallizes in the triclinic space group P 1 ¯ with the lattice parameters a = 663.71(5) pm, b = 1024.32(7) pm, c = 1057.49(8) pm, α = 81.034(2)°, β = 87.468(2)°, γ = 89.237(2)° and Z = 2. There are two distinct Sc3+ positions, which show six-fold coordination by oxygen atoms as [ScO6]9− octahedra (d(Sc–O) = 205–212 pm). Three different [Se2O5]2− anions provide these oxygen atoms with their terminal ligands (Ot). Each of the six selenium(IV) central atoms exhibit a stereochemically active lone pair of electrons, so that all [Se2O5]2− anions consist of two ψ1-tetrahedral [SeO3]2− subunits (d(Se–Ot) = 164–167 pm, d(Se–Ob) = 176–185 pm, ∢(O–Se–O) = 93–104°) sharing one bridging oxygen atom (Ob) with ∢(Se–Ob–Se) = 121–128°. The vibrational modes of the complex anionic [Se2O5]2− entities were characterized via single-crystal Raman spectroscopy
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CsCu2Sc3Te6 and CsCuY2Te4: Two new quaternary cesium copper rare-earth metal tellurides
Solid State Sciences, 2010Co-Authors: Jean‐marie Babo, Thomas SchleidAbstract:Abstract The two new quaternary cesium copper(I) rare-earth metal(III) tellurides CsCu2Sc3Te6 and CsCuY2Te4 were prepared at 900 °C by reacting the elements copper, Scandium or yttrium and tellurium together with CsBr as flux and cesium source for fourteen days in evacuated torch-sealed silica ampoules. Both Compounds crystallize in space group C2/m of the monoclinic system with unit cells of the dimensions a = 1777.63(9), b = 414.20(2), c = 1033.51(5) pm, β = 113.032(4)° for CsCu2Sc3Te6 (Z = 2) and a = 3741.90(19), b = 432.73(2), c = 2087.62(11) pm, β = 107.357(4)° for CsCuY2Te4 (Z = 12). The crystal structure of the Scandium Compound contains [CuTe4]7− tetrahedra, which are cis-edge connected in order to build up 1 ∞ { [ CuTe 1 / 1 t Te 3 / 3 e ] 3 − } chains, and [ScTe6]9− octahedra, which share edges and vertices in forming corrugated 2 ∞ { [ Sc 3 Te 6 ] 3 − } layers. These layers are separated from each other by [CuTe4]7− tetrahedra and Cs+ cations in trans-face bicapped square-prismatic Te2− coordination (CN = 10). The yttrium Compound has a three-dimensional structure as well built up of [CuTe4]7− tetrahedra and [YTe6]9− octahedra. All three crystallographically independent Cu+ cations reside in an individual infinite 1 ∞ { [ CuTe 2 / 1 t Te 2 / 2 v ] 5 − } chain, in which each [CuTe4]7− tetrahedron shares two vertices with neighbouring ones. The anionic framework 3 ∞ { [ Y 2 Te 4 ] 2 − } and the copper-bearing 3 ∞ { [ CuY 2 Te 4 ] − } one consist of sixteen-membered ring channels containing three different types of Cs+ cations (two in each channel) with bicapped trigonal prismatic (CN = 8) and monocapped cubic Te2− coordination (CN = 9). Thus there is no isotypy with the KCuGd2S4-type structure, characteristic for the lighter chalcogens (e. g. ACuM2Ch4; A = K–Cs, M = La–Er, Ch = S and Se).
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Cs3NdSi8O19 und Cs6Nd2Si21O48: Zwei cäsiumhaltige Oxosilicate des Neodyms im Vergleich / Cs3NdSi8O19 and Cs6Nd2Si21O48: Two Caesium-containing Oxosilicates of Neodymium in Comparison
Zeitschrift für Naturforschung B, 2009Co-Authors: Marion C. Schäfer, Thomas SchleidAbstract:In the quaternary system Cs / Nd / Si / O, two new representatives, the phyllo-oxosilicate Cs3NdSi8O19 and the tecto-oxosilicate Cs6Nd2Si21O48, were synthesized by CsF-flux-supported solid-state reactions between Nd2O3 and SiO2. The first one, Cs3NdSi8O19 (orthorhombic, Cmcm (no. 63), a = 705.74(5), b = 2712.85(19), c = 1163.72(8) pm, Z = 4), is not isotypic to the related Scandium Compound Cs3ScSi8O19. The [SiO4]4− tetrahedra (d(Si4+ -O2−) = 156 -163 pm) in the structure of Cs3NdSi8O19 are connected via common corners to form corrugated, loop-branched double layers containing four- and eight-membered rings in the (010) plane and eight-membered rings along [001]. Each of the eight-membered ellipses emerging along [100] is additionally loopbranched by two four-membered chains. The oxosilicate double layers are cross-linked by vertexsharing via otherwise isolated [NdO6]9− octahedra (d(Nd3+-O2-)= 232 - 234 pm) to build up a three-dimensional framework. Also in between the oxosilicate double layers, the (Cs1)+ cations are located on the 8 f site. Each of the octagonal channels along [001] hosts one (Cs3)+ and two (Cs2)+ cations, which both reside at only partially occupied sites (8g and 8 f , respectively) and disorder, because otherwise too short Cs+ ・ ・ ・ Cs+ distances would occur. The second Compound, Cs6Nd2Si21O48, crystallizes also in an orthorhombic space group (Pmmn (no. 59), a = 2189.24(15), b = 731.92(5), c = 1593.61(11) pm, Z = 2). Starting from a loop-branched single layer containing five- and eight-membered rings, a three-dimensional framework of vertex-shared [SiO4]4− tetrahedra (d(Si4+-O2−) = 149 - 164 pm) built up, in which the Si-O distances range from 149 to 164 pm within a broad range. In certain cavities, one kind of Nd3+, but four kinds of Cs+ cations (here, all sites with full occupation) are embedded. Also surrounded by only six O2− anions just like in the first case, the Nd3+ cations (d(Nd3+-O2−) = 233 - 237 pm) exhibit an unusually small, but not unknown coordination sphere for this relatively large lanthanoid(III) cation
Stefan Greiner - One of the best experts on this subject based on the ideXlab platform.
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Sc2[Se2O5]3: The First Rare-Earth Metal Oxoselenate(IV) with Exclusively [Se2O5]2− Anions
Crystals, 2018Co-Authors: Stefan Greiner, Thomas SchleidAbstract:The Scandium oxodiselenate(IV) Sc2[Se2O5]3 was synthesized via solid-state reactions between Scandium sesquioxide (Sc2O3) and selenium dioxide (SeO2) with thallium(I) chloride (TlCl) as fluxing agent in molar ratios of 1:4:2. Evacuated fused silica ampoules were used as reactions vessels for annealing the mixtures for five days at 800 °C. The new Scandium Compound crystallizes in the triclinic space group P 1 ¯ with the lattice parameters a = 663.71(5) pm, b = 1024.32(7) pm, c = 1057.49(8) pm, α = 81.034(2)°, β = 87.468(2)°, γ = 89.237(2)° and Z = 2. There are two distinct Sc3+ positions, which show six-fold coordination by oxygen atoms as [ScO6]9− octahedra (d(Sc–O) = 205–212 pm). Three different [Se2O5]2− anions provide these oxygen atoms with their terminal ligands (Ot). Each of the six selenium(IV) central atoms exhibit a stereochemically active lone pair of electrons, so that all [Se2O5]2− anions consist of two ψ1-tetrahedral [SeO3]2− subunits (d(Se–Ot) = 164–167 pm, d(Se–Ob) = 176–185 pm, ∢(O–Se–O) = 93–104°) sharing one bridging oxygen atom (Ob) with ∢(Se–Ob–Se) = 121–128°. The vibrational modes of the complex anionic [Se2O5]2− entities were characterized via single-crystal Raman spectroscopy.
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Sc2[Se2O5]3: The First Rare-Earth Metal Oxoselenate(IV) with Exclusively [Se2O5]2− Anions
MDPI AG, 2018Co-Authors: Stefan Greiner, Thomas SchleidAbstract:The Scandium oxodiselenate(IV) Sc2[Se2O5]3 was synthesized via solid-state reactions between Scandium sesquioxide (Sc2O3) and selenium dioxide (SeO2) with thallium(I) chloride (TlCl) as fluxing agent in molar ratios of 1:4:2. Evacuated fused silica ampoules were used as reactions vessels for annealing the mixtures for five days at 800 °C. The new Scandium Compound crystallizes in the triclinic space group P 1 ¯ with the lattice parameters a = 663.71(5) pm, b = 1024.32(7) pm, c = 1057.49(8) pm, α = 81.034(2)°, β = 87.468(2)°, γ = 89.237(2)° and Z = 2. There are two distinct Sc3+ positions, which show six-fold coordination by oxygen atoms as [ScO6]9− octahedra (d(Sc–O) = 205–212 pm). Three different [Se2O5]2− anions provide these oxygen atoms with their terminal ligands (Ot). Each of the six selenium(IV) central atoms exhibit a stereochemically active lone pair of electrons, so that all [Se2O5]2− anions consist of two ψ1-tetrahedral [SeO3]2− subunits (d(Se–Ot) = 164–167 pm, d(Se–Ob) = 176–185 pm, ∢(O–Se–O) = 93–104°) sharing one bridging oxygen atom (Ob) with ∢(Se–Ob–Se) = 121–128°. The vibrational modes of the complex anionic [Se2O5]2− entities were characterized via single-crystal Raman spectroscopy
Tomomi Ujihara - One of the best experts on this subject based on the ideXlab platform.
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Highly selective recognition of tryptophan in water by a poorly water-soluble Scandium Compound
Tetrahedron Letters, 2015Co-Authors: Nobuyuki Hayashi, Shigeki Jin, Tomomi UjiharaAbstract:Abstract In order to recognize aromatic α-amino acids in water using a poorly water-soluble artificial receptor, a new Scandium Compound was synthesized. This receptor had high affinities for tryptophan (Trp) and lysine (Lys). Due to a rate difference in the complex formation process, high selectivity for Trp was achieved. Geometry optimizations using ωB97XD density functional theory (DFT) calculations revealed that Trp was thoroughly included in the receptor with intermolecular forces of the Sc/O coordination bond, aromatic/aromatic interactions, and NH/O interaction in addition to the hydrophobic effect and van der Waals attractive force. In the complex between Lys and the receptor Compound, the Sc/O coordination bond, ionic NH/O interactions, CH/π interaction, and NH/π interactions were found along with the hydrophobic effect and van der Waals attractive force.
Nobuyuki Hayashi - One of the best experts on this subject based on the ideXlab platform.
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Highly selective recognition of tryptophan in water by a poorly water-soluble Scandium Compound
Tetrahedron Letters, 2015Co-Authors: Nobuyuki Hayashi, Shigeki Jin, Tomomi UjiharaAbstract:Abstract In order to recognize aromatic α-amino acids in water using a poorly water-soluble artificial receptor, a new Scandium Compound was synthesized. This receptor had high affinities for tryptophan (Trp) and lysine (Lys). Due to a rate difference in the complex formation process, high selectivity for Trp was achieved. Geometry optimizations using ωB97XD density functional theory (DFT) calculations revealed that Trp was thoroughly included in the receptor with intermolecular forces of the Sc/O coordination bond, aromatic/aromatic interactions, and NH/O interaction in addition to the hydrophobic effect and van der Waals attractive force. In the complex between Lys and the receptor Compound, the Sc/O coordination bond, ionic NH/O interactions, CH/π interaction, and NH/π interactions were found along with the hydrophobic effect and van der Waals attractive force.
Glenn P. A. Yap - One of the best experts on this subject based on the ideXlab platform.
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Terphenyl ligand systems in lanthanide chemistry: use of the 2,6-di(1-naphthyl)phenyl ligand for the synthesis of kinetically stabilized complexes of trivalent ytterbium, thulium, and yttrium.
Inorganic chemistry, 2001Co-Authors: Gerd W. Rabe, Christian D. Berube, Glenn P. A. YapAbstract:The molecular structures of terphenyl derivatives of trivalent ytterbium, thulium, and yttrium of general composition DnpLnCl2(THF)2 [Dnp = 2,6-di(1-naphthyl)phenyl] are reported. The complexes (Ln = Yb: 1; Ln = Tm: 2; Ln = Y: 3) are synthesized by reaction of 1 equiv of DnpLi with 1 equiv of LnCl3 (Ln = Yb, Tm, or Y) in tetrahydrofuran at room temperature in 50% yield. Attempts to prepare a Dnp Scandium Compound gave heterobimetallic [(THF)3Sc2OCl5Li(THF)]2 (4) in low yield. 1 crystallizes in the monoclinic space group C2/c. Crystal data for 1 at 203 K: a = 14.333(3) A, b = 16.353(3) A, c = 12.427(2) A, β = 91.021(4)°, Z = 4, Dcalcd = 1.637 g cm-3, R1 = 4.44%. 2 crystallizes in the monoclinic space group C2/c. Crystal data for 2 at 203 K: a = 14.333(1) A, b = 16.374(2) A, c = 12.404(1) A, β = 90.934(2)°, Z = 4, Dcalcd = 1.628 g cm-3, R1 = 3.00%. 3 crystallizes in the monoclinic space group C2/c. Crystal data for 3 at 203 K: a = 14.348(3) A, b = 16.476(3) A, c = 12.356(2) A, β = 90.987(4)°, Z = 4, D...
