Polyselenide chemistry of indium and thallium in dimethylformamide, acetonitrile, and water. Syntheses, structures, and properties of the new complexes [In2(Se4)4(Se5)]4-, [In2Se2(Se4)2]2-, [In3Se3(Se4)3]3-, and [Tl ...

Sandeep S. Dhingra, Mercouri G Kanatzidis

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Abstract

Full title: Polyselenide chemistry of indium and thallium in dimethylformamide, acetonitrile, and water. Syntheses, structures, and properties of the new complexes [In2(Se4)4(Se5)]4-, [In2Se2(Se4)2]2-, [In3Se3(Se4)3]3-, and [Tl3Se3(Se4)3]3-. The reaction of InCl3 with Na2Se5 in dimethylformamide (DMF) in the presence of Ph4PCl gave (Ph4P)4[In2(Se4)4(Se 5)] (I) in 75% yield. Under the same conditions, InCl3 reacted with Na2Se5 in the presence of Pr4NBr or Et4NBr and afforded (Pr4N)4[In2(Se4)4(Se 5)] (II) in 65% yield and (Et4N)4[In2(Se4)4(Se 5)] (III) in 72% yield, respectively. (I) crystallizes in the triclinic space group P1 (No. 2) with unit cell dimensions a = 11.417(4) Å, b = 12.734(9) Å, c = 20.188(9) Å, α = 96.03(5)°, β = 94.69(3)°, γ =111.68(4)°, V = 2689(2) Å3, Z = 1, and R/Rw = 0.073/0.085. (II) crystallizes in the monoclinic space group P2/c (No. 13) with unit cell dimensions a = 15.997(3) Å, b = 17.376(3) Å, c = 15.168(2) Å, β = 94.56(3)°, V = 4202(1) Å3, Z = 2, and R/Rw = 0.069/0.080. (III) crystallizes in the triclinic space group P1 (No. 2) with unit cell dimensions a = 12.428(3) Å, b = 15.781(3) Å, c = 17.540(4) Å, α = 89.47(2)°, β = 97.90(2)°, γ = 94.47(2)°, V = 3397(1) Å3, Z = 2, and R/Rw = 0.075/0.084. Single-crystal X-ray diffraction studies show that (I), (II), and (III) contain the same anion, [In2(Se4)4(Se5)]4-. The anion consists of In3+ centers in trigonal bipyramidal coordination; each In atom is chelated by two bidentate Se42- ligands forming a [In(Se4)2]- unit. Two of these [In(Se4)2]- units are bridged by an Se52- chain forming a dimer. The hydrothermal reaction of InCl3 with Na2Se4 in the presence of Pr4NBr and water at 110°C for 3 days in an evacuated sealed Pyrex tube afforded deep red crystals of (Pr4N)2[In2Se2(Se4) 2] (IV), in 80% yield. Under the same conditions the reaction with [(Ph3P)2N]Cl yields [(Ph3P)2N]2[In2Se 2(Se4)2] (V) in 60% yield. (IV) crystallizes in the triclinic space group P1 (No. 2) with unit cell dimensions a = 8.938(2) Å, b = 11.290(2) Å, c = 11.528(2) Å, α = 79.19(1)°, β = 105.56(1)°, γ = 99.84(1)°, V = 1093(1) Å3, Z = 1, and R/Rw = 0.045/0.049. (V) also crystallizes in the triclinic space group P1 (No. 2) with unit cell dimensions a = 10.931(5) Å, b = 11.302(7) Å, c = 15.189(8) Å, α = 84.98(5)°, β = 94.15(4)°, γ = 93.86(4)°, V = 1858(1) Å3, Z = 1, and R/Rw = 0.060/0.081. Single-crystal X-ray diffraction studies show that (IV) and (V) contain the same binuclear anion [In2Se2(Se4)2]2-. The anion contains In3+ with a tetrahedral coordination, bridged by two monoselenides to form a planar [In2Se2]2+ core with an inversion center at the middle of the In-In vector of 3.336(2) Å. The remaining two coordination sites on each In atom are occupied by the Se42- bidentate chelates. The reaction of InCl3 with Na2Se5 in 1:2 mole ratio in acetonitrile in the presence of Et4NBr afforded (Et4N)3[In3Se3(Se4) 3] (VI). Similar reaction of TlCl with Na2Se5 in 1:2 mole ratio in DMF in the presence of Et4NBr gave (Et4N)3[Tl3Se3(Se4) 3] (VII). Single-crystal X-ray diffraction studies show that the two compounds (VI) and (VII) are isostructural and crystallize in the monoclinic space group P21/c (No. 14). The unit cell dimensions are a = 16.747(4) Å, b = 13.701(3) Å, c = 22.227(3) Å, β = 94.16(2)°, V = 5086(2) Å3, Z = 4, and R/Rw = 0.045/0.051 and a = 16.813(3) Å, b = 13.774(3) Å, c = 22.186(4) Å, β = 94.13(1)°; V = 5126(2) Å3, Z = 4, and R/Rw = 0.072/0.087 for (VI) and (VII), respectively. The trinuclear anion [M3Se3(Se4)3]3- (M = In, Tl) in (VI) and (VII) contains M3+ with a tetrahedral coordination. Each M3+ center has a chelating Se42- ligand and is bridged to the other two M3+ centers by monoselenide, Se2-, ligands forming a six-membered [M3Se3]3+ core. Variable-temperature 77Se NMR spectra of (I)-(VII) are reported. All indium-polyselenide complexes show the same NMR spectrum at room temperature in DMF suggesting that in solution only one In/Se species exists. UV/vis of (I)-(III) are similar, with two absorptions at ∼450 and ∼650 nm, while (IV)-(VII) have a featureless spectra. The electrochemistry of (I) and (VI) is reported. The solid-state far-IR spectra of all the compounds show strong absorptions in the 300-100 cm-1 region due to the Se-Se and M-Se stretching frequencies; tentative assignments are reported herein. Thermal gravimetric analysis data show that the compounds pyrolyze to give single-phase binary metal chalcogenides (β-In2Se3 and TlSe).

Original languageEnglish
Pages (from-to)1350-1362
Number of pages13
JournalInorganic Chemistry
Volume32
Issue number8
Publication statusPublished - 1993

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Dimethylformamide
Indium
Thallium
thallium
acetonitrile
Anions
indium
chemistry
Water
anions
synthesis
cells
water
Single crystals
Ligands
X ray diffraction
ligands
Nuclear magnetic resonance
single crystals
Chalcogenides

ASJC Scopus subject areas

  • Inorganic Chemistry

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@article{5d8242ff44cc407c812495298ff1cfbf,
title = "Polyselenide chemistry of indium and thallium in dimethylformamide, acetonitrile, and water. Syntheses, structures, and properties of the new complexes [In2(Se4)4(Se5)]4-, [In2Se2(Se4)2]2-, [In3Se3(Se4)3]3-, and [Tl ...",
abstract = "Full title: Polyselenide chemistry of indium and thallium in dimethylformamide, acetonitrile, and water. Syntheses, structures, and properties of the new complexes [In2(Se4)4(Se5)]4-, [In2Se2(Se4)2]2-, [In3Se3(Se4)3]3-, and [Tl3Se3(Se4)3]3-. The reaction of InCl3 with Na2Se5 in dimethylformamide (DMF) in the presence of Ph4PCl gave (Ph4P)4[In2(Se4)4(Se 5)] (I) in 75{\%} yield. Under the same conditions, InCl3 reacted with Na2Se5 in the presence of Pr4NBr or Et4NBr and afforded (Pr4N)4[In2(Se4)4(Se 5)] (II) in 65{\%} yield and (Et4N)4[In2(Se4)4(Se 5)] (III) in 72{\%} yield, respectively. (I) crystallizes in the triclinic space group P1 (No. 2) with unit cell dimensions a = 11.417(4) {\AA}, b = 12.734(9) {\AA}, c = 20.188(9) {\AA}, α = 96.03(5)°, β = 94.69(3)°, γ =111.68(4)°, V = 2689(2) {\AA}3, Z = 1, and R/Rw = 0.073/0.085. (II) crystallizes in the monoclinic space group P2/c (No. 13) with unit cell dimensions a = 15.997(3) {\AA}, b = 17.376(3) {\AA}, c = 15.168(2) {\AA}, β = 94.56(3)°, V = 4202(1) {\AA}3, Z = 2, and R/Rw = 0.069/0.080. (III) crystallizes in the triclinic space group P1 (No. 2) with unit cell dimensions a = 12.428(3) {\AA}, b = 15.781(3) {\AA}, c = 17.540(4) {\AA}, α = 89.47(2)°, β = 97.90(2)°, γ = 94.47(2)°, V = 3397(1) {\AA}3, Z = 2, and R/Rw = 0.075/0.084. Single-crystal X-ray diffraction studies show that (I), (II), and (III) contain the same anion, [In2(Se4)4(Se5)]4-. The anion consists of In3+ centers in trigonal bipyramidal coordination; each In atom is chelated by two bidentate Se42- ligands forming a [In(Se4)2]- unit. Two of these [In(Se4)2]- units are bridged by an Se52- chain forming a dimer. The hydrothermal reaction of InCl3 with Na2Se4 in the presence of Pr4NBr and water at 110°C for 3 days in an evacuated sealed Pyrex tube afforded deep red crystals of (Pr4N)2[In2Se2(Se4) 2] (IV), in 80{\%} yield. Under the same conditions the reaction with [(Ph3P)2N]Cl yields [(Ph3P)2N]2[In2Se 2(Se4)2] (V) in 60{\%} yield. (IV) crystallizes in the triclinic space group P1 (No. 2) with unit cell dimensions a = 8.938(2) {\AA}, b = 11.290(2) {\AA}, c = 11.528(2) {\AA}, α = 79.19(1)°, β = 105.56(1)°, γ = 99.84(1)°, V = 1093(1) {\AA}3, Z = 1, and R/Rw = 0.045/0.049. (V) also crystallizes in the triclinic space group P1 (No. 2) with unit cell dimensions a = 10.931(5) {\AA}, b = 11.302(7) {\AA}, c = 15.189(8) {\AA}, α = 84.98(5)°, β = 94.15(4)°, γ = 93.86(4)°, V = 1858(1) {\AA}3, Z = 1, and R/Rw = 0.060/0.081. Single-crystal X-ray diffraction studies show that (IV) and (V) contain the same binuclear anion [In2Se2(Se4)2]2-. The anion contains In3+ with a tetrahedral coordination, bridged by two monoselenides to form a planar [In2Se2]2+ core with an inversion center at the middle of the In-In vector of 3.336(2) {\AA}. The remaining two coordination sites on each In atom are occupied by the Se42- bidentate chelates. The reaction of InCl3 with Na2Se5 in 1:2 mole ratio in acetonitrile in the presence of Et4NBr afforded (Et4N)3[In3Se3(Se4) 3] (VI). Similar reaction of TlCl with Na2Se5 in 1:2 mole ratio in DMF in the presence of Et4NBr gave (Et4N)3[Tl3Se3(Se4) 3] (VII). Single-crystal X-ray diffraction studies show that the two compounds (VI) and (VII) are isostructural and crystallize in the monoclinic space group P21/c (No. 14). The unit cell dimensions are a = 16.747(4) {\AA}, b = 13.701(3) {\AA}, c = 22.227(3) {\AA}, β = 94.16(2)°, V = 5086(2) {\AA}3, Z = 4, and R/Rw = 0.045/0.051 and a = 16.813(3) {\AA}, b = 13.774(3) {\AA}, c = 22.186(4) {\AA}, β = 94.13(1)°; V = 5126(2) {\AA}3, Z = 4, and R/Rw = 0.072/0.087 for (VI) and (VII), respectively. The trinuclear anion [M3Se3(Se4)3]3- (M = In, Tl) in (VI) and (VII) contains M3+ with a tetrahedral coordination. Each M3+ center has a chelating Se42- ligand and is bridged to the other two M3+ centers by monoselenide, Se2-, ligands forming a six-membered [M3Se3]3+ core. Variable-temperature 77Se NMR spectra of (I)-(VII) are reported. All indium-polyselenide complexes show the same NMR spectrum at room temperature in DMF suggesting that in solution only one In/Se species exists. UV/vis of (I)-(III) are similar, with two absorptions at ∼450 and ∼650 nm, while (IV)-(VII) have a featureless spectra. The electrochemistry of (I) and (VI) is reported. The solid-state far-IR spectra of all the compounds show strong absorptions in the 300-100 cm-1 region due to the Se-Se and M-Se stretching frequencies; tentative assignments are reported herein. Thermal gravimetric analysis data show that the compounds pyrolyze to give single-phase binary metal chalcogenides (β-In2Se3 and TlSe).",
author = "Dhingra, {Sandeep S.} and Kanatzidis, {Mercouri G}",
year = "1993",
language = "English",
volume = "32",
pages = "1350--1362",
journal = "Inorganic Chemistry",
issn = "0020-1669",
publisher = "American Chemical Society",
number = "8",

}

TY - JOUR

T1 - Polyselenide chemistry of indium and thallium in dimethylformamide, acetonitrile, and water. Syntheses, structures, and properties of the new complexes [In2(Se4)4(Se5)]4-, [In2Se2(Se4)2]2-, [In3Se3(Se4)3]3-, and [Tl ...

AU - Dhingra, Sandeep S.

AU - Kanatzidis, Mercouri G

PY - 1993

Y1 - 1993

N2 - Full title: Polyselenide chemistry of indium and thallium in dimethylformamide, acetonitrile, and water. Syntheses, structures, and properties of the new complexes [In2(Se4)4(Se5)]4-, [In2Se2(Se4)2]2-, [In3Se3(Se4)3]3-, and [Tl3Se3(Se4)3]3-. The reaction of InCl3 with Na2Se5 in dimethylformamide (DMF) in the presence of Ph4PCl gave (Ph4P)4[In2(Se4)4(Se 5)] (I) in 75% yield. Under the same conditions, InCl3 reacted with Na2Se5 in the presence of Pr4NBr or Et4NBr and afforded (Pr4N)4[In2(Se4)4(Se 5)] (II) in 65% yield and (Et4N)4[In2(Se4)4(Se 5)] (III) in 72% yield, respectively. (I) crystallizes in the triclinic space group P1 (No. 2) with unit cell dimensions a = 11.417(4) Å, b = 12.734(9) Å, c = 20.188(9) Å, α = 96.03(5)°, β = 94.69(3)°, γ =111.68(4)°, V = 2689(2) Å3, Z = 1, and R/Rw = 0.073/0.085. (II) crystallizes in the monoclinic space group P2/c (No. 13) with unit cell dimensions a = 15.997(3) Å, b = 17.376(3) Å, c = 15.168(2) Å, β = 94.56(3)°, V = 4202(1) Å3, Z = 2, and R/Rw = 0.069/0.080. (III) crystallizes in the triclinic space group P1 (No. 2) with unit cell dimensions a = 12.428(3) Å, b = 15.781(3) Å, c = 17.540(4) Å, α = 89.47(2)°, β = 97.90(2)°, γ = 94.47(2)°, V = 3397(1) Å3, Z = 2, and R/Rw = 0.075/0.084. Single-crystal X-ray diffraction studies show that (I), (II), and (III) contain the same anion, [In2(Se4)4(Se5)]4-. The anion consists of In3+ centers in trigonal bipyramidal coordination; each In atom is chelated by two bidentate Se42- ligands forming a [In(Se4)2]- unit. Two of these [In(Se4)2]- units are bridged by an Se52- chain forming a dimer. The hydrothermal reaction of InCl3 with Na2Se4 in the presence of Pr4NBr and water at 110°C for 3 days in an evacuated sealed Pyrex tube afforded deep red crystals of (Pr4N)2[In2Se2(Se4) 2] (IV), in 80% yield. Under the same conditions the reaction with [(Ph3P)2N]Cl yields [(Ph3P)2N]2[In2Se 2(Se4)2] (V) in 60% yield. (IV) crystallizes in the triclinic space group P1 (No. 2) with unit cell dimensions a = 8.938(2) Å, b = 11.290(2) Å, c = 11.528(2) Å, α = 79.19(1)°, β = 105.56(1)°, γ = 99.84(1)°, V = 1093(1) Å3, Z = 1, and R/Rw = 0.045/0.049. (V) also crystallizes in the triclinic space group P1 (No. 2) with unit cell dimensions a = 10.931(5) Å, b = 11.302(7) Å, c = 15.189(8) Å, α = 84.98(5)°, β = 94.15(4)°, γ = 93.86(4)°, V = 1858(1) Å3, Z = 1, and R/Rw = 0.060/0.081. Single-crystal X-ray diffraction studies show that (IV) and (V) contain the same binuclear anion [In2Se2(Se4)2]2-. The anion contains In3+ with a tetrahedral coordination, bridged by two monoselenides to form a planar [In2Se2]2+ core with an inversion center at the middle of the In-In vector of 3.336(2) Å. The remaining two coordination sites on each In atom are occupied by the Se42- bidentate chelates. The reaction of InCl3 with Na2Se5 in 1:2 mole ratio in acetonitrile in the presence of Et4NBr afforded (Et4N)3[In3Se3(Se4) 3] (VI). Similar reaction of TlCl with Na2Se5 in 1:2 mole ratio in DMF in the presence of Et4NBr gave (Et4N)3[Tl3Se3(Se4) 3] (VII). Single-crystal X-ray diffraction studies show that the two compounds (VI) and (VII) are isostructural and crystallize in the monoclinic space group P21/c (No. 14). The unit cell dimensions are a = 16.747(4) Å, b = 13.701(3) Å, c = 22.227(3) Å, β = 94.16(2)°, V = 5086(2) Å3, Z = 4, and R/Rw = 0.045/0.051 and a = 16.813(3) Å, b = 13.774(3) Å, c = 22.186(4) Å, β = 94.13(1)°; V = 5126(2) Å3, Z = 4, and R/Rw = 0.072/0.087 for (VI) and (VII), respectively. The trinuclear anion [M3Se3(Se4)3]3- (M = In, Tl) in (VI) and (VII) contains M3+ with a tetrahedral coordination. Each M3+ center has a chelating Se42- ligand and is bridged to the other two M3+ centers by monoselenide, Se2-, ligands forming a six-membered [M3Se3]3+ core. Variable-temperature 77Se NMR spectra of (I)-(VII) are reported. All indium-polyselenide complexes show the same NMR spectrum at room temperature in DMF suggesting that in solution only one In/Se species exists. UV/vis of (I)-(III) are similar, with two absorptions at ∼450 and ∼650 nm, while (IV)-(VII) have a featureless spectra. The electrochemistry of (I) and (VI) is reported. The solid-state far-IR spectra of all the compounds show strong absorptions in the 300-100 cm-1 region due to the Se-Se and M-Se stretching frequencies; tentative assignments are reported herein. Thermal gravimetric analysis data show that the compounds pyrolyze to give single-phase binary metal chalcogenides (β-In2Se3 and TlSe).

AB - Full title: Polyselenide chemistry of indium and thallium in dimethylformamide, acetonitrile, and water. Syntheses, structures, and properties of the new complexes [In2(Se4)4(Se5)]4-, [In2Se2(Se4)2]2-, [In3Se3(Se4)3]3-, and [Tl3Se3(Se4)3]3-. The reaction of InCl3 with Na2Se5 in dimethylformamide (DMF) in the presence of Ph4PCl gave (Ph4P)4[In2(Se4)4(Se 5)] (I) in 75% yield. Under the same conditions, InCl3 reacted with Na2Se5 in the presence of Pr4NBr or Et4NBr and afforded (Pr4N)4[In2(Se4)4(Se 5)] (II) in 65% yield and (Et4N)4[In2(Se4)4(Se 5)] (III) in 72% yield, respectively. (I) crystallizes in the triclinic space group P1 (No. 2) with unit cell dimensions a = 11.417(4) Å, b = 12.734(9) Å, c = 20.188(9) Å, α = 96.03(5)°, β = 94.69(3)°, γ =111.68(4)°, V = 2689(2) Å3, Z = 1, and R/Rw = 0.073/0.085. (II) crystallizes in the monoclinic space group P2/c (No. 13) with unit cell dimensions a = 15.997(3) Å, b = 17.376(3) Å, c = 15.168(2) Å, β = 94.56(3)°, V = 4202(1) Å3, Z = 2, and R/Rw = 0.069/0.080. (III) crystallizes in the triclinic space group P1 (No. 2) with unit cell dimensions a = 12.428(3) Å, b = 15.781(3) Å, c = 17.540(4) Å, α = 89.47(2)°, β = 97.90(2)°, γ = 94.47(2)°, V = 3397(1) Å3, Z = 2, and R/Rw = 0.075/0.084. Single-crystal X-ray diffraction studies show that (I), (II), and (III) contain the same anion, [In2(Se4)4(Se5)]4-. The anion consists of In3+ centers in trigonal bipyramidal coordination; each In atom is chelated by two bidentate Se42- ligands forming a [In(Se4)2]- unit. Two of these [In(Se4)2]- units are bridged by an Se52- chain forming a dimer. The hydrothermal reaction of InCl3 with Na2Se4 in the presence of Pr4NBr and water at 110°C for 3 days in an evacuated sealed Pyrex tube afforded deep red crystals of (Pr4N)2[In2Se2(Se4) 2] (IV), in 80% yield. Under the same conditions the reaction with [(Ph3P)2N]Cl yields [(Ph3P)2N]2[In2Se 2(Se4)2] (V) in 60% yield. (IV) crystallizes in the triclinic space group P1 (No. 2) with unit cell dimensions a = 8.938(2) Å, b = 11.290(2) Å, c = 11.528(2) Å, α = 79.19(1)°, β = 105.56(1)°, γ = 99.84(1)°, V = 1093(1) Å3, Z = 1, and R/Rw = 0.045/0.049. (V) also crystallizes in the triclinic space group P1 (No. 2) with unit cell dimensions a = 10.931(5) Å, b = 11.302(7) Å, c = 15.189(8) Å, α = 84.98(5)°, β = 94.15(4)°, γ = 93.86(4)°, V = 1858(1) Å3, Z = 1, and R/Rw = 0.060/0.081. Single-crystal X-ray diffraction studies show that (IV) and (V) contain the same binuclear anion [In2Se2(Se4)2]2-. The anion contains In3+ with a tetrahedral coordination, bridged by two monoselenides to form a planar [In2Se2]2+ core with an inversion center at the middle of the In-In vector of 3.336(2) Å. The remaining two coordination sites on each In atom are occupied by the Se42- bidentate chelates. The reaction of InCl3 with Na2Se5 in 1:2 mole ratio in acetonitrile in the presence of Et4NBr afforded (Et4N)3[In3Se3(Se4) 3] (VI). Similar reaction of TlCl with Na2Se5 in 1:2 mole ratio in DMF in the presence of Et4NBr gave (Et4N)3[Tl3Se3(Se4) 3] (VII). Single-crystal X-ray diffraction studies show that the two compounds (VI) and (VII) are isostructural and crystallize in the monoclinic space group P21/c (No. 14). The unit cell dimensions are a = 16.747(4) Å, b = 13.701(3) Å, c = 22.227(3) Å, β = 94.16(2)°, V = 5086(2) Å3, Z = 4, and R/Rw = 0.045/0.051 and a = 16.813(3) Å, b = 13.774(3) Å, c = 22.186(4) Å, β = 94.13(1)°; V = 5126(2) Å3, Z = 4, and R/Rw = 0.072/0.087 for (VI) and (VII), respectively. The trinuclear anion [M3Se3(Se4)3]3- (M = In, Tl) in (VI) and (VII) contains M3+ with a tetrahedral coordination. Each M3+ center has a chelating Se42- ligand and is bridged to the other two M3+ centers by monoselenide, Se2-, ligands forming a six-membered [M3Se3]3+ core. Variable-temperature 77Se NMR spectra of (I)-(VII) are reported. All indium-polyselenide complexes show the same NMR spectrum at room temperature in DMF suggesting that in solution only one In/Se species exists. UV/vis of (I)-(III) are similar, with two absorptions at ∼450 and ∼650 nm, while (IV)-(VII) have a featureless spectra. The electrochemistry of (I) and (VI) is reported. The solid-state far-IR spectra of all the compounds show strong absorptions in the 300-100 cm-1 region due to the Se-Se and M-Se stretching frequencies; tentative assignments are reported herein. Thermal gravimetric analysis data show that the compounds pyrolyze to give single-phase binary metal chalcogenides (β-In2Se3 and TlSe).

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