A novel coordination polymer [(C8H20N)(Ag2I3)]n ([C8H20N]+ = tetraethyl ammo- nium (TEA)) was synthesized by the reaction of AgI and C8H20NI at room temperature with pH = 6.5, and structurally characterized by means o...A novel coordination polymer [(C8H20N)(Ag2I3)]n ([C8H20N]+ = tetraethyl ammo- nium (TEA)) was synthesized by the reaction of AgI and C8H20NI at room temperature with pH = 6.5, and structurally characterized by means of X-ray single-crystal diffraction. It crystallizes in orthorhombic, space group Pna21 with a = 7.3323(9), b = 18.250(2), c =12.5294(15) ?, C6.33H16.16NAg2I3, Mr = 702.76, V = 1676.6(4) ?3, Z = 4, Dc = 2.784 g/cm3, F(000) = 1256.6, μ(MoKα) = 7.828 mm-1, the final R = 0.0529 and wR = 0.1586 for 1189 observed reflections with I > 2σ(I). X-ray analysis shows that the [Ag2I3]n- chain is built up by AgI4 tetrahedron and in combination with quaternary ammonium cations ([C8H20N]+) by static attractive forces to form the so-called organic-inorganic hybrid material.展开更多
A silver iodide, （ipq）4Ag418 1, has been synthesized in the presence of ipq （ipq = N-（isopentyl）-quinolinium） acting as a structure-directing reagent （SDA）. Compound 1 crystallizes in the triclinic system, spa...A silver iodide, （ipq）4Ag418 1, has been synthesized in the presence of ipq （ipq = N-（isopentyl）-quinolinium） acting as a structure-directing reagent （SDA）. Compound 1 crystallizes in the triclinic system, space group PT, with a = 9.850（2）, b = 11.564（2）, c = 16.111（3） ,A ,α = 104.64（3）, β = 105.73（3）, γ = 94.37（3）o, V= 1688.3（7） A^3, Z = 2, D,= 2.205 g/cm^3, F（000） = 1042, C28H33Ag2l4N2, Mr= 1120.90, μ（MoKa） = 4.836 mm^-1, the final R = 0.0363 and wR = 0.0761 for 5465 observed reflections with 1 〉 2σ（I）. 1 consists of uncoordinated structure-directing molecule and inorganic moiety tuned by organic SDA. Tetrameric Ag4I8^4- anion in 1 is composed of edgesharing AgI4 tetrahedra and AgI3 planar triangles. Electrostatic interaction between organic counter cations and inorgan!c moieties is present and contributes to the crystal packing. 1 was further characterized with IR, UV-Vis, elemental analysis and cyclic voltammetry. Based on the crystal structure data, quantum chemical calculation with DFr method was used to reveal the electronic structure and optical property of 1.展开更多
Methylammonium lead iodide,as related organometal halide perovskites,emerged recently as a particularly attractive material for photovoltaic applications.The origin of its appealing properties is sometimes assigned to...Methylammonium lead iodide,as related organometal halide perovskites,emerged recently as a particularly attractive material for photovoltaic applications.The origin of its appealing properties is sometimes assigned to its potential ferroelectric character,which remains however a topic of intense debate.Here,we rationalize from first-principles calculations how the spatial arrangement of methylammonium polar molecules is progressively constrained by the subtle interplay between their tendency to bond with the inorganic framework and the appearance of iodine octahedra rotations inherent to the perovskite structure.The disordered tetragonal phase observed at room temperature is paraelectric.We show that it should a priori become ferroelectric but that iodine octahedra rotations drive the system toward an antipolar orthorhombic ground state,making it a missed ferroelectric.展开更多
A simple ammonium iodide salt in amide solvent catalyzes regioselective decarboxylative alkylation of C(sp^(3))-H bonds of Naryl glycine derivatives, of C(sp^(2))-H bond of heteroarenes, and cascade radical addition t...A simple ammonium iodide salt in amide solvent catalyzes regioselective decarboxylative alkylation of C(sp^(3))-H bonds of Naryl glycine derivatives, of C(sp^(2))-H bond of heteroarenes, and cascade radical addition to unsaturated bond followed by intramolecular addition to arene, with a broad scope of N-hydroxyphthalimide derived redox active esters under visible light irradiation. The reactions are suggested to proceed through photoactivation of a transiently assembled chromophore from electron-deficient phthalimide moiety and iodide anion through an anion-π interaction in solvent cage followed by diffusion to generate solvated free radical species to react with C-H substrates. The simplicity, practicality, and broad substrate scope of this method highlight the synthetic power of photocatalysis through transiently assembled chromophore, and will hopefully inspire further developments of low cost photocatalysis based on various non-covalent interactions, which are prevalent in supramolecular chemistry and biosystems, for sustainable organic synthesis.展开更多
Anhydrous EuI2 is an essential raw material for novel Eu^2＋-doped halide scintillators such as SrI2：Eu, CsBa2I5：Eu and BaBrI ：Eu. An efficient and economic method to produce high purity anhydrous EuI2 is critical ...Anhydrous EuI2 is an essential raw material for novel Eu^2＋-doped halide scintillators such as SrI2：Eu, CsBa2I5：Eu and BaBrI ：Eu. An efficient and economic method to produce high purity anhydrous EuI2 is critical for future development and applications of these scintillators. In this paper, the ammonium-iodide route to anhydrous EuI2 was investigated, and anhydrous EuI2 with purity of 99.95 wt.% was successfully prepared. The dehydration mechanisms of europium iodide hydrate and its mixture with NH4I were comparatively investigated by X-ray diffraction（XRD）, thermal analysis and fluorescence spectroscopy. The thermal decomposition process of individual europium iodide hydrate was revealed as follows： EuI3·9H2O→EuI 3·8H2O→EuI 3·7H2O→EuI 2·H2O→EuI2, and the hydrolysis mechanism of europium hydrate was comprehensively studied. When europium iodide hydrate was dehydrated with NH4I, NH4Eu2I5 formed as an intermediate product, and the hydrolysis of EuI2 was effectively restrained. The role of NH4I as an iodination agent was also discussed.展开更多
A study on liquidliquid extraction of palladium based on KIethanol in the presence of ammonium sulphate was performed.The results showed that PdI42- can be easily extracted into the ethanol phase.Common io...A study on liquidliquid extraction of palladium based on KIethanol in the presence of ammonium sulphate was performed.The results showed that PdI42- can be easily extracted into the ethanol phase.Common ions,such as Fe(Ⅲ),Al(Ⅲ),Zn(Ⅱ),Mn(Ⅱ),Ni(Ⅱ),Cr(Ⅲ),and Co(Ⅱ),could not be extracted into the ethanol phase and do not interfere with the determination of Pd(Ⅱ) at pH45.展开更多
基金This work was supported by the Foundation of Education Committee of Fujian Province (JB03053, JB04016)
文摘A novel coordination polymer [(C8H20N)(Ag2I3)]n ([C8H20N]+ = tetraethyl ammo- nium (TEA)) was synthesized by the reaction of AgI and C8H20NI at room temperature with pH = 6.5, and structurally characterized by means of X-ray single-crystal diffraction. It crystallizes in orthorhombic, space group Pna21 with a = 7.3323(9), b = 18.250(2), c =12.5294(15) ?, C6.33H16.16NAg2I3, Mr = 702.76, V = 1676.6(4) ?3, Z = 4, Dc = 2.784 g/cm3, F(000) = 1256.6, μ(MoKα) = 7.828 mm-1, the final R = 0.0529 and wR = 0.1586 for 1189 observed reflections with I > 2σ(I). X-ray analysis shows that the [Ag2I3]n- chain is built up by AgI4 tetrahedron and in combination with quaternary ammonium cations ([C8H20N]+) by static attractive forces to form the so-called organic-inorganic hybrid material.
文摘A silver iodide, （ipq）4Ag418 1, has been synthesized in the presence of ipq （ipq = N-（isopentyl）-quinolinium） acting as a structure-directing reagent （SDA）. Compound 1 crystallizes in the triclinic system, space group PT, with a = 9.850（2）, b = 11.564（2）, c = 16.111（3） ,A ,α = 104.64（3）, β = 105.73（3）, γ = 94.37（3）o, V= 1688.3（7） A^3, Z = 2, D,= 2.205 g/cm^3, F（000） = 1042, C28H33Ag2l4N2, Mr= 1120.90, μ（MoKa） = 4.836 mm^-1, the final R = 0.0363 and wR = 0.0761 for 5465 observed reflections with 1 〉 2σ（I）. 1 consists of uncoordinated structure-directing molecule and inorganic moiety tuned by organic SDA. Tetrameric Ag4I8^4- anion in 1 is composed of edgesharing AgI4 tetrahedra and AgI3 planar triangles. Electrostatic interaction between organic counter cations and inorgan!c moieties is present and contributes to the crystal packing. 1 was further characterized with IR, UV-Vis, elemental analysis and cyclic voltammetry. Based on the crystal structure data, quantum chemical calculation with DFr method was used to reveal the electronic structure and optical property of 1.
基金W.-Y.T.acknowledges the support from F.R.S.-FNRS Belgium.J.-Z.Z.acknowledges the support from the Startup Funding for Outstanding Young Scientist of South China Normal University and the financial support of China Scholarship Council(Grant No.202006755025)The authors acknowledge access to the CECI supercomputer facilities funded by the F.R.S-FNRS(Grant No.2.5020.1)the Tier-1 supercomputer of the Federation Wallonie-Bruxelles funded by the Walloon Region(Grant No.1117545).
文摘Methylammonium lead iodide,as related organometal halide perovskites,emerged recently as a particularly attractive material for photovoltaic applications.The origin of its appealing properties is sometimes assigned to its potential ferroelectric character,which remains however a topic of intense debate.Here,we rationalize from first-principles calculations how the spatial arrangement of methylammonium polar molecules is progressively constrained by the subtle interplay between their tendency to bond with the inorganic framework and the appearance of iodine octahedra rotations inherent to the perovskite structure.The disordered tetragonal phase observed at room temperature is paraelectric.We show that it should a priori become ferroelectric but that iodine octahedra rotations drive the system toward an antipolar orthorhombic ground state,making it a missed ferroelectric.
基金supported by the National Natural Science Foundation of China(GG2065010002)and KY(2060000119)support from the Fundamental Research Funds for the Central Universities(WK2060120003)Anhui Provincial Natural Science Foundation(1908085QB53)。
文摘A simple ammonium iodide salt in amide solvent catalyzes regioselective decarboxylative alkylation of C(sp^(3))-H bonds of Naryl glycine derivatives, of C(sp^(2))-H bond of heteroarenes, and cascade radical addition to unsaturated bond followed by intramolecular addition to arene, with a broad scope of N-hydroxyphthalimide derived redox active esters under visible light irradiation. The reactions are suggested to proceed through photoactivation of a transiently assembled chromophore from electron-deficient phthalimide moiety and iodide anion through an anion-π interaction in solvent cage followed by diffusion to generate solvated free radical species to react with C-H substrates. The simplicity, practicality, and broad substrate scope of this method highlight the synthetic power of photocatalysis through transiently assembled chromophore, and will hopefully inspire further developments of low cost photocatalysis based on various non-covalent interactions, which are prevalent in supramolecular chemistry and biosystems, for sustainable organic synthesis.
基金supported by the National Basic Research Program of China(2012CBA01207)National Natural Science Foundation of China(51402021)
文摘Anhydrous EuI2 is an essential raw material for novel Eu^2＋-doped halide scintillators such as SrI2：Eu, CsBa2I5：Eu and BaBrI ：Eu. An efficient and economic method to produce high purity anhydrous EuI2 is critical for future development and applications of these scintillators. In this paper, the ammonium-iodide route to anhydrous EuI2 was investigated, and anhydrous EuI2 with purity of 99.95 wt.% was successfully prepared. The dehydration mechanisms of europium iodide hydrate and its mixture with NH4I were comparatively investigated by X-ray diffraction（XRD）, thermal analysis and fluorescence spectroscopy. The thermal decomposition process of individual europium iodide hydrate was revealed as follows： EuI3·9H2O→EuI 3·8H2O→EuI 3·7H2O→EuI 2·H2O→EuI2, and the hydrolysis mechanism of europium hydrate was comprehensively studied. When europium iodide hydrate was dehydrated with NH4I, NH4Eu2I5 formed as an intermediate product, and the hydrolysis of EuI2 was effectively restrained. The role of NH4I as an iodination agent was also discussed.
文摘A study on liquidliquid extraction of palladium based on KIethanol in the presence of ammonium sulphate was performed.The results showed that PdI42- can be easily extracted into the ethanol phase.Common ions,such as Fe(Ⅲ),Al(Ⅲ),Zn(Ⅱ),Mn(Ⅱ),Ni(Ⅱ),Cr(Ⅲ),and Co(Ⅱ),could not be extracted into the ethanol phase and do not interfere with the determination of Pd(Ⅱ) at pH45.
