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131.
The Courses of the Ammonolyses of the Ammonium Hexafluorometalates of Aluminum, Gallium, and Indium, (NH4)3MF6 (M = Al, Ga, In) The courses of the ammonolysis reactions of the ammonium hexafluorometalates (NH4)3MF6 (M = Al, Ga, In) were investigated with the aid of in‐situ powder diffractometry and differential thermal analysis. Under these conditions, the reaction of (NH4)3AlF6 with gaseous ammonia yields at about 360 °C AlF3 via the intermediates NH4AlF4, Al(NH3)2F3 and Al(NH3)F3. The ammonolysis of (NH4)3GaF6 produces GaN at about 400 °C. Depending upon the actual reaction conditions, the intermediates NH4GaF4 and Ga(NH3)F3 as well as their ammonia adducts NH4GaF4 · NH3 and Ga(NH3)2F3 and the amide‐ammoniate Ga(NH3)(NH2)F2 are observed. In the case of (NH4)3InF6 the intermediates (NH4)3InF6 · NH3 and In(NH3)F3 may exist; there are also indications for the reduction of In(III) to In(I) and for the existence of In(NH3)2F and InF as products of the ammonolysis of (NH4)3InF6. 相似文献
132.
Reactions of R4Sb2 (R = Me, Et) with (Me3SiCH2)3M (M = Ga, In) and Crystal Structures of [(Me3SiCH2)2InSbMe2]3 and [(Me3SiCH2)2GaOSbEt2]2 The reaction of (Me3SiCH2)3In with Me2SbSbMe2 gives [(Me3SiCH2)2InSbMe2]3 ( 1 ) and Me3SiCH2SbMe2. [(Me3SiCH2)2GaOSbEt2]2 ( 2 ) is formed by the reaction of (Me3SiCH2)3Ga with Et2SbSbEt2 and oxygen. The syntheses and the crystal structures of 1 and 2 are reported. 相似文献
133.
Gerald Linti Wolfgang Kstler Holger Piotrowski Alexander Rodig 《Angewandte Chemie (International ed. in English)》1998,37(16):2209-2211
Classical and nonclassical can be used to describe the bonding in the polyhedral Ga4Si framework of the silagallanate ion [Me3SiSi{GaSi(SiMe3)3}3GaSiMe3]− (the GaSi framework is depicted in the picture). This is the result of density functional calculations that were carried out on model compounds. The cluster was obtained by ultrasonication of gallium and iodine and subsequent reaction with (Me3Si)3Li(thf)3. 相似文献
134.
Sesquialkoxides of Gallium and Indium Treatment of GaMe3 with one equivalent of HOcHex in toluene at 20 °C leads to [Me2GaOcHex]2 ( 4 ) under evolution of methane. The reaction of InMe3 with two equivalents of HOcHex leads under similar conditions not to [MeIn(OcHex)2]n but to the sesquialkoxide [In{Me2In(OcHex)2}3] ( 5 ). 5 can be described also as [{Me2InOcHex)}2{MeIn(OcHex)2}2]. The use of an excess of cyclohexanol in boiling toluene gives the same result. Under these reflux conditions, the reaction of GaMe3 with an excess of PhCH2OH leads exclusively to another type of sequialkoxides, [Ga{MeGa(OCH2Ph)3}3] ( 6 ). 4 — 6 were characterized by NMR, vibrational and MS spectra, as well as by X‐ray structure determinations. According to this, 4 forms centrosymmetrical and therefore planar Ga2O2 four‐membered rings. 5 and 6 possess basically the same structural motif, central M3+ ion ( 5 : In3+; 6 : Ga3+) coordinated by three metalate units ( 5 : [Me2In(OcHex)2]—; 6 : [MeGa(OCH2Ph)3]—). The central M3+ ions have always coordination number (CN) six while the three surrounding metal ions possess CN 4. Because of the spectroscopic findings 6 must exist in two isomers (1:1). The C3‐symmetrical isomer C3‐ 6 was characterized by X‐ray analysis, while the isomer C1‐ 6 could by described mainly by the complex NMR data. 相似文献
135.
Chemical Vapor Transport of Solid Solutions. 11 Mixed Phases and Chemical Vapor Transport in the Systems CrIII/InIII/GeIV/O, GaIII/InIII/GeIV/O, MnIII/InIII/GeIV/O und FeIII/InIII/GeIV/O By means of chemical vapor transport methods the following mixed phases have been prepared: Cr0, 18In1, 82Ge2O7 (Cl2, 950 → 850 °C), (Ga0, 6In1, 4)2Ge2O7 (Thortveitit‐type, Cl2, 1050 → 950 °C), (Ga1, 9In0, 1)2Ge2O7 (Ga2Ge2O7‐type, 1050 → 950 °C), (In1, 9Mn0, 1)2Ge2O7 (Thortveiti‐type, Cl2, 1000 → 800 °C), mixed phase crystallizing in the Mn2Ge2O7‐structure showing a composition near MnInGe2O7 (Cl2, 1000 → 800 °C), Mn6, 5In0, 5GeO12 (Braunit‐type, Cl2, 1000 → 800 °C), (FexIn1‐x)Ge2O7 (Thortveitit‐type with x = 0…0, 94; Cl2, 840 → 780 °C). Changing the compositions of the starting materials showed no effect on the composition of the deposit except for the system Fe2O3‐In2O3‐GeO2. 相似文献
136.
Werner Uhl Lars Cuypers Gertraud Geiseler Klaus Harms Werner Massa 《无机化学与普通化学杂志》2002,628(5):1001-1006
Syntheses and Crystal Structures of Dialkylgallium Hydrides — Dimeric versus Trimeric Formula Units Dialkylgallium hydrides (R = Me, Et, iPr, iBu, neopentyl) were obtained on two different synthetic routes. The dimethyl and diethyl compounds were formed by the reaction of LiH with the corresponding dialkylgallium chlorides via lithium dialkyldihydridogallate intermediates, which so far have not been isolated in a pure form. On the second route, trialkylgallium compounds were treated with [GaH3·NMe2Et] to yield the dialkylgallium hydrides by a substituent exchange reaction. The dimethyl, diethyl and diisopropyl compounds are trimeric in solution. That trimeric structure was verified for the diisopropyl derivative by a crystal structure determination. Di(neopentyl)gallium hydride has a dimeric structure in solution and in the solid state. 相似文献
137.
Structural Characterization of Bis(metallated) Derivatives of 3, 3‐Dimethyl‐1, 5‐bis(trimethylsilyl)‐1, 5‐diaza‐pentane with Lithium and Aluminum and of two Donor‐substituted Digallanes The diaminopropane derivative Me2C[CH2N(H)SiMe3]2 is metallated with n‐butyllithium and lithium tetrahydridoaluminate to obtain Me2C[CH2N(Li)SiMe3]2 and Me2C[CH2N(Li)SiMe3][CH2N(AlH2)SiMe3], respectively. Both compounds exhibit a central eight‐membered ring, Li4N4 or Li2Al2N4. Me2C[CH2N(Li)SiMe3]2 reacts with Ga2Cl4 · 2dioxane under formation of the corresponding tetra(amino)digallane. This is monomeric, in contrast to a dimeric tetraalkoxy‐substituted digallane, Ga4OtBu8. All compounds were characterized by single crystal X‐ray crystallography. 相似文献
138.
Alexander Donchev Andreas Schnepf Elke Baum Gregor Stßer Hansgeorg Schnckel 《无机化学与普通化学杂志》2002,628(1):157-161
[Ga6R8]2– (R = SiPh2Me): A Metalloid Cluster Compound with an Unexpected Ga6‐Frame The reaction of a metastable solution of GaBr with a solution of LiSiPh2Me in a toluene/THF mixture results in orange coloured crystals of [Ga6(SiPh2Me)8]2– · 2 [Li(THF)4]+ ( 1 ). The unexpected structure of the planar Ga6 frame (C2h) could also be realized with the help of DFT calculation. DFT calculations furthermore show that 1 is energetically favoured against an octahedral Ga6R62– species and R2. In contrast calculations for the similar Al and B species show that in these cases the octahedral entities are favoured. These results demonstrate that even for similar compounds of B, Al, and Ga Wade rules are too general and that they cannot predict the correct structure. Moreover the atomic arrangement within 1 shows that a structure is preferred which is also present in allotropic β‐Ga and that therefore clusters of this type should be called metalloid or more general elementoid. 相似文献
139.
140.
S. Anfang J. Grebe M. Mhlen B. Neumüller N. Faza W. Massa J. Magull K. Dehnicke 《无机化学与普通化学杂志》1999,625(8):1395-1400
Synthesis and Crystal Structures of the Phosphoraneiminato Complexes [AlCl2(NPEt3)]2, [GaI2(NPEt3)]2, and [GaI2(NPPh3)]2 [AlCl2(NPEt3)]2 ( 1 ) is made according to the known method by reaction of aluminium trichloride with the silylated phosphaneimine Me3SiNPEt3 in acetonitrile; it is isolated as colourless, moisture sensitive crystals. The phosphoraneiminato complexes [GaI2(NPEt3)]2 ( 2 ) and [GaI2(NPPh3)]2 ( 3 ), on the other hand, are obtained by redox reactions as pale yellow crystals; ( 2 ) of “gallium(I) iodide” with Me3SiNPEt3 in toluene and ( 3 ) of gallium with N-iodine triphenylphosphaneimine, INPPh3, in tetrahydrofuran. 1 and 3 are characterized spectroscopically and by crystal structure determinations; 2 is characterized only crystallographically. 1 : Space group Pbca, Z = 4; lattice dimensions at –70 °C: a = 1232.6(2), b = 1341.1(2), c = 1393.4(3) pm, R1 = 0.0315. 1 forms centrosymmetric molecules in which the Al atoms are linked via Al–N bonds of the two (NPEt3–) groups; with 185.0 and 184.4 pm these bonds are of almost the same lengths. 2 : Space group Pbca, Z = 4; lattice dimensions at –80 °C: a = 1380.0(1), b = 1311.0(1), c = 1429.1(1) pm, R1 = 0.0273. 2 crystallizes isotypically with 1 . The gallium atoms of the centrosymmetric Ga2N2 four-membered ring are connected with Ga–N distances of equal length (190.9 pm). 3 · THF: Space group P212121, Z = 2; lattice dimensions at –140 °C: a = 1494.6(1), b = 1536.3(1), c = 974.6(1) pm, R1 = 0.0382. 3 forms dimeric molecules in which the gallium atoms are linked via the N atoms of the (NPPh3–) groups to form a non-planar Ga2N2 four-membered ring of C2 symmetry with Ga–N bonds of equal lengths – within standard deviations – of 194.7 pm. The phosphoraneiminato groups are arranged in a synperiplanar way. 相似文献