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171.
172.
N. Schneider M. Frégnaux M. Bouttemy F. Donsanti A. Etcheberry D. Lincot 《Materials Today Chemistry》2018
Gallium sulfide (GaxS) and copper gallium sulfide (CuxGaySz) were synthetized by atomic layer deposition (ALD), using copper acetylacetonate Cu(acac)2, hexakis(dimethylamino)digallium [Ga(NMe2)3]2 and hydrogen sulfide (H2S). Thanks to the compatibility of the CuxS and GaxS ALD windows, a supercycle strategy that combines single growth cycles of the two binary compounds was used to generate the ternary material. A wide range of compositions and properties can be obtained from Ga-rich to Cu-rich via copper gallium sulfide thin films. Structural, morphological, and optoelectronic characterizations were performed on all films. Surface and in-depth chemical compositions were determined by X-ray photoelectron spectroscopy profiling, allowing a better understanding of the chemical reactions involved during the growth process. In the case of GaxS films, other Ga precursors have been tested. Our experimental observations, combined with reported ones and density functional theory calculation results have highlighted the specific reactivity of alkylamido precursor in ALD chemistry. Compositional studies revealed a significant O content which origin is discussed and represents an important challenge to address in ALD of sulfide materials in general. 相似文献
173.
Mercury(I) chloride reacts with gallium(III) chloride in benzene/1, 2‐dichlorobenzene solution to give the binuclear compound Hg2(GaCl4)2 ( 1 ). Reduction of mercury(I) chloride with mercury in gallium(III) chloride‐benzene mixture leads to the trinuclear compound Hg3(GaCl4)2 ( 2 ). The crystal structures of 1 and 2 were determined by single‐crystal X‐ray diffraction {Hg2(GaCl4)2: triclinic, P1¯, a = 645.21(3), b = 654.44(3), c = 927.17(7) pm, α = 83.526(2)°, β = 74.915(2)°, γ = 61.863(3)°; Hg3(GaCl4)2: monoclinic, P21/c, a = 715.79(1), b = 1501.59(4), c = 1421.43(4) pm, β = 98.9798(9)°}. 相似文献
174.
The gallium monohydride (GaH) molecule and its positive ion were theoretically investigated by abinitio molecular orbital
calculations with a flexible basis set including g-type functions on the Ga atom. Electron correlations among not only the valence electrons of Ga 4s4p and H 1s but also the semi-core electrons of Ga 3d were incorporated by a size-consistent scheme of the coupled pair approximation. The contribution of the 3d electron correlation was found to be considerable on spectroscopic constants of both GaH and GaH+, especially on the bond length.
Received: 25 July 1997 / Accepted: 13 November 1997 相似文献
175.
A sensitive and selective flow injection time-based method for on-line preconcentration/separation and determination of gallium by flame atomic absorption spectrometry at trace levels was developed. The on-line formed gallium chloride complex is sorbed onto a polyether-type polyurethane foam mini-column, followed by on-line quantitative elution with isobutyl methyl ketone and direct introduction into the flame pneumatic nebulizer of the atomic absorption spectrometer. All chemical and flow variables of the system as well as the possible interferences were studied. The manner of strong HCl solutions propulsion was investigated and established using a combination of two displacement bottles. For 90 s preconcentration time, a sample frequency of 28 h−1, an enhancement factor of 40, a detection limit of 6 μg l−1 and a precision expressed as relative standard deviation (sr) of 3.3% (at 1.00 mg l−1) were achieved. The calibration curve is linear over the concentration range 0.02-3.00 mg l−1. The accuracy of the developed method was sufficient and evaluated by the analysis of a silicon-aluminum alloy standard reference material. Finally, it was successfully applied to gallium determination in commercial aluminum alloys, natural waters and urine. 相似文献
176.
Hossein Aghabozorg Farshid Ramezanipour Parvaneh D. Kheirollahi Ali A. Saei Ardeshir Shokrollahi Mojtaba Shamsipur Faranak Manteghi Janet Soleimannejad Mahboubeh A. Sharif 《无机化学与普通化学杂志》2006,632(1):147-154
Three new complexes of group thirteen metals, gallium(III), indium(III), and thallium(III) with proton transfer compounds, obtained from 2,6‐pyridinedicarboxylic acid (dipicolinic acid), were synthesized and characterized using elemental analysis, IR, 1H and 13C NMR spectroscopy and single crystal X‐ray diffraction. The gallium(III) and indium(III) complexes were prepared using (pydaH2)(pydc) (pyda = 2,6‐pyridinediamine, pydcH2 = dipicolinic acid) and thallium(III) complex was obtained from (creatH)(pydcH) (creat = creatinine). The chemical formulae and space groups of the complexes are (pydaH)[Ga(pydc)2] · 3.25H2O · CH3OH, ( 1 ), [In(pydc)(pydcH)(H2O)2] · 5H2O, Pna21 ( 2 ) and [Tl2(pydcH)3(pydc)(H2O)2], ( 3 ). Non‐covalent interactions such as ion‐pairing, hydrogen bonding and π‐π stacking are discussed. The complexation reactions of pyda, pydc, and pyda + pydc with In3+ and Ga3+ ions in aqueous solution were investigated by potentiometric pH titrations, and the equilibrium constants for all major complexes formed are described. 相似文献
177.
For elimination of copper interference in anodic stripping determinations of zinc at mercury and bismuth film electrodes gallium ions are usually added to the supporting electrolyte. In the presented studies novel ex situ formed gallium film electrode was applied for this purpose. The proposed electrode is less toxic than mercury one while the detection limit for zinc was lower than for bismuth film electrode following the same deposition time. The calibration graph for deposition time of 60 s was linear from 5 × 10−8 to 2 × 10−6 mol L−1. The determinations of zinc were carried out from undeaerated solutions. The proposed procedure was applied to zinc determination in certified reference material and tap water sample. 相似文献
178.
Ryo Amemiya 《Tetrahedron letters》2004,45(22):4333-4335
Lithiated N-benzylanilines were ethynylated at the ortho-position with silylchloroethyne at 120 °C in the presence of a catalytic amount of GaCl3. Trimethylsilylated N-methylaniline could also be used for this transformation. 相似文献
179.
Shamik Ghoshal Dimple P. Dutta Munirathinam Nethaji 《Journal of organometallic chemistry》2006,691(26):5838-5844
Several gallium and indium dithiocarboxylate complexes of the type [MenM(S2CR)3−n] (M = Ga, In; n = 0, 1, 2; R = phenyl (Ph), p-tolyl (tol), mesityl (Mes)) have been synthesized. These complexes were characterized by elemental analysis, IR, UV-vis and NMR (1H,13C{1H}) spectroscopy. Structure of [MeGa(S2Ctol)2] was established by X-ray crystallography. The gallium atom adopts a distorted five coordinate geometry which is intermediate between trigonal bipyramidal and square pyramidal configurations. The complex [Me2InS2Ctol] underwent a two-step thermal decomposition leading to the formation of tetragonal β-In2S3. 相似文献
180.
邻氯苯基荧光酮—溴化十六烷基三甲铵—β—环糊精荧光熄灭法测定痕量镓 总被引:10,自引:0,他引:10
本文研究了在溴化十六烷基三甲铵和β-环糊精的存在下,以邻氯苯荧光酮作为荧光试剂,用荧光熄灭法测定痕量镓的新方法,详细研究了反应的条件,反应适宜酸度范围为PH=3.8-5.0,镓含量在4-60ng/ml范围内呈线性关系,本法的灵敏度高,检测限为2.4ng/ml可用于地质试样中镓的测定,结果满意。 相似文献