scholarly journals Doping Reaction of some Nanotubes with Aluminium Atom: A Thermodynamic PM6 and ONIOM Investigation

2017 ◽  
Vol 33 (1) ◽  
pp. 329-334
Author(s):  
Nasrin Zeighami ◽  
Mohammad Reza Gholami ◽  
Asadollah Boshra
Keyword(s):  
Aluminium Atom

Dissecting the Effects of Water Guest Adsorption and Framework Breathing on the AlO4(OH)2 Centers of Metal-Organic Framework MIL-53 (Al) by Solid State NMR and Structural Analysis

2021 ◽  
Author(s):  
Alexander G. Stepanov ◽  
Alexander E. Khudozhitkov ◽  
Sergei S. Arzumanov ◽  
Alexander V. Toktarev ◽  
Svetlana Cherepanova ◽  
...  
Keyword(s):  
Solid State Nmr ◽  
Metal Organic Framework ◽  
Structural Phase ◽  
Quadrupole Coupling Constant ◽  
Coupling Constant ◽  
Aluminium Atom ◽  
Quadrupole Coupling ◽  
Adsorption Of Water ◽  
Metal Organic ◽  
The Relationship

The relationship between the adsorption of water on MIL-53 (Al) MOF, the structural phase of MIL-53 (Al), and quadrupole coupling constant of 27Al framework aluminium atom (QCC) of the MOF...

Das Anion [R2Al-AlR2Br]- (R = CH(SiMe3)2) mit Aluminium-Aluminium- und terminaler Aluminium-Brom-Bindung / The Anion [R2Al-AlR2Br]- (R = CH(SiMe3)2) with an Aluminium -Aluminium and a Terminal Aluminium -Bromine Bond

1994 ◽  
Vol 49 (5) ◽  
pp. 637-641 ◽  
Author(s):  
Werner Uhl ◽  
Uwe Schütz ◽  
Siegfried Pohl ◽  
Wolfgang Saak
Keyword(s):  
Crystal Structure ◽  
Bond Length ◽  
Structure Determination ◽  
Crystal Structure Determination ◽  
Aluminium Atom ◽  
Ethereal Solution ◽  
Quantitative Formation ◽  
Starting Compound

Tetrakis[bis(trimethylsilyl)methyl]dialane(4) (1) with an Al-Al bond reacts with LiBr in n-pentane in the presence of chelating N.N.N'.N'-tetramethylethylenediamine (TMEDA) to yield the monobromo adduct [Li(TMEDA)2]+[R2Al-AlR2Br]- 4. Compound 4 is unstable in ethereal solution and decomposes with quantitative formation of LiBr and the starting compound 1. Crystal structure determination of 4 C5H10 shows a terminal Al-Br bond in an anion with a four-coordinated aluminium atom neighbouring a three-coordinated, coordinatively unsaturated aluminium atom. While the Al-Al bond length is not significantly different (264.3 pm) as compared to the data for 1, the Al-Br bond is rather long (247.6 pm) indicating a weak coordinative bonding.

scholarly journals The spectra of doubly- and trebly-ionised phosphorus (P III and P IV)

1925 ◽  
Vol 108 (746) ◽  
pp. 332-343 ◽  
Keyword(s):  
Neutral Atom ◽  
Limited Range ◽  
Magnesium Atom ◽  
Aluminium Atom ◽  
Group V ◽  
Lower Stage ◽  
Three Stages ◽  
Approximate Wave ◽  
Two Stages

Previous to the classification of some of the lines of the phosphorus spectrum into series of the doubly-ionised atom, which is described in the present paper, no series had been observed for the elements of group V of the periodic table. The element phosphorus of this group was selected for investigation because the spectrum corresponding to each stage of ionisation was expected to bear a marked resemblance to that of the silicon atom of one lower stage of ionisation, of the aluminium atom of two stages lower, of the magnesium atom of three stages lower, and so on. The series corresponding to successive stages of ionisation of some of these atoms had already been worked out, and hence, if the series spectra of phosphorus could be observed, a direct comparison would be possible. The spectrum of the neutral atom of phosphorus has been identified and described by the present writer, but no series relationships have been found. This is probably due to the limited range of the spectrum which it has been possible to investigate so far. The region investigated by Geuter in 1907 extends from λ 5727·90 to λ 2389·93 and contains 530 lines which are ascribed to phosphorus. Kayser gives also the approximate wave-lengths of a few more lines at the red end up to λ 6505. Only four of these lines belong to the arc spectrum, and the rest are therefore lines of phosphorus at one or more stages of ionisation.

Cyclische Diazastannylene, XXX [1] Symmetrisch und asymmetrisch substituierte German- und Stannandiyle mit Amid-, Alkoholat- und Thiolat-Liganden, Teil I [2] / Cyclic Diazastannylenes, XXX [1] Symmetrically and Asymmetrically Substituted Germane- and Stannanediyls with Amide, Alcoholate and Thiolate Ligands, Part I [2]

1989 ◽  
Vol 44 (9) ◽  
pp. 1067-1081 ◽  
Author(s):  
M. Veith ◽  
P. Hobein ◽  
R. Rösler
Keyword(s):  
Chelate Ring ◽  
Membered Ring ◽  
Aluminium Atom ◽  
X Ray ◽  
Thiolate Ligands ◽  
Trigonal Bipyramidal ◽  
Tetrahedral Environment ◽  
Homologous Compounds ◽  
Structure Determinations ◽  
Tert Butylamine

Chelates of Ge(II) and Sn(II)Symmetrically and unsymmetrically substituted germane- and stannanediyls as well as chelated bis(amino)- or aminooxogermanium- and -tinmonohalides have been obtained from cyclic bis(amino)germane- and stannanediyls by treatment with tert-butylamine, tert-butanol and tert-butylmercaptane. The following compounds have been synthesized: GeX2 (X = OtBu (5), StBu (6)), Sn(StBu), (9), GeXCl (X = N(H)tBu (21), OtBu (22)), SnXCl (X = N(H)tBu (23), OtBu (24), StBu (25), OMe (28)) and Sn(OtBu)Br (27). In the series of the chelates Me2Si(NtBu)(NHtBu)GeCl (13), Me2Si(NtBu)(OtBu)SnX (X = Cl (18), OMe (19)) and the bischelate [Me2Si(NtBu)(OtBu)]2Sn (20) have been prepared. When 18 is allowed to react with aluminiumtrimethyl Me2Si(NtBu)(OtBu)AlClMe is formed, a compound with a center of chirality at the aluminium atom. X-ray structure determinations have been performed on single crystals of 6, 8, 9, 13, 22 and 24. 6, 8, 22 and 24 form molecular dimers with c.n. of 3 at the Ge or Sn atoms, resp. While the tBu-S ligands are syn with respect to the central Ge2S2 ring in 6 (symmetry approaching C2v), the tBu-O ligands are anti to the central Sn2O2 ring in 8 (symmetry Ci). 9 forms a coordination polymer with all Sn atoms in a Ψ-trigonal-bipyramidal and all S atoms in a Ψ-tetrahedral environment. The germanium atom in 13 is coordinated by a chlorine, a λ3- and a λ4-nitrogen atom, the two nitrogen atoms being connected by as dimethylsilyl group. The hydrogen and chlorine atom of 13 are found at the same side of the four-membered chelate ring. The two unsymmetrically substituted, homologous compounds Ge(O/tBu)Cl (22) and Sn(OtBu)Cl (24) are found to form dimers via O→Ge resp. O→Sn bonds. While the chlorine atoms in 22 are syn with respect to the four-membered ring, they are anti in the case of molecule 24.

scholarly journals Tris(6-tert-butyl-4-methylpyridazine-3-thiolato-κ2N,S)aluminium

IUCrData ◽  
2016 ◽  
Vol 1 (12) ◽  
Author(s):  
Stefan Holler ◽  
Ferdinand Belaj ◽  
Nadia C. Mösch-Zanetti
Keyword(s):  
Intermolecular Interactions ◽  
Title Complex ◽  
Aluminium Atom ◽  
Tert Butyl ◽  
Octahedral Environment

The title complex, [Al(C9H13N2S)3], is composed of an aluminium atom coordinated by three bidentate thiopyridazine ligands in an octahedral environment. It has approximateC3symmetry, with Al—N distances in the range 1.9732 (17)–1.9794 (17) Å and three Al—S distances in the range 2.3961 (8)–2.4354 (8) Å. In the crystal, there are no significant intermolecular interactions present.

scholarly journals In silico search for planar hexacoordinate Silicon atom: A kinetically viable species

2021 ◽  
Author(s):  
Amlan Kalita ◽  
Shahnaz Rohman ◽  
Chayanika Kashyap ◽  
Sabnam Ullah ◽  
Indrani Baruah ◽  
...  
Keyword(s):  
Silicon Atom ◽  
In Silico ◽  
Density Functional ◽  
Local Minimum ◽  
Global Minimum ◽  
Kinetic Studies ◽  
Coupled Cluster ◽  
Aluminium Atom ◽  
Multiple Bonds ◽  
Functional Theory

In silico search for planar hexacoordinate silicon center has been initiated by global minimum screening with density functional theory and energy refinement using coupled cluster theory. The search resulted in a local minimum of SiAl3Mg3H2+ structure which contains a planar hexacoordinate silicon center (phSi). The phSi structure is 5.8 kcal/mol higher in energy than the global minimum. However, kinetic studies reveal that the local minimum structure has enough stability to be detected experimentally. Born-Oppenheimer molecular dynamics (BOMD) simulations reveal that the phSi structure can be maintained up to 400 K. The formation of multiple bonds between the central silicon atom and framework aluminium atom is the key stabilizing factor for the planar structure.

A ReaxFF potential for Al - ZnO systems

2022 ◽  
Author(s):  
Iain Brown ◽  
Roger Smith ◽  
Steven David Kenny
Keyword(s):  
Density Functional ◽  
Normal Incidence ◽  
Oxide System ◽  
Binding Energies ◽  
Bulk Crystals ◽  
Aluminium Atom ◽  
Functional Theory ◽  
Reactive Field ◽  
Low Energies ◽  
Cohesive Energies

Abstract A reactive field force (ReaxFF) potential has been created in order to model the structural effects of low percentage dopant aluminium in a zinc oxide system. The potential’s parameters were fitted to configurations computed with Density Functional Theory (DFT): cohesive energies, binding energies and forces were all considered for bulk crystals, surface structures and ZnAl alloys. As a first application of the model, the energetic deposition (0.1 - 40 eV) of an aluminium atom onto the polar surface of a ZnO (000 ̄1) is considered. For low energies the Al atom attaches to two preferred sites on the surface but as the energy increases above ≈ 15 eV subplantation is preferred at near normal incidence, with high diffusion barriers between stable sites. At these energies, reflection of the Al atom occurs at incident angles above ≈ 55◦.

Studying on Rare Earth Aluminizing Process of GH4169 Superalloy

2011 ◽  
Vol 314-316 ◽  
pp. 267-272 ◽  
Author(s):  
Jun Ming Luo ◽  
Ji Lin Xu ◽  
Li Ping Deng
Keyword(s):  
Rare Earth ◽  
High Temperature ◽  
Oxidation Resistance ◽  
Crystalline Phase ◽  
High Temperature Oxidation ◽  
Micro Hardness ◽  
Aluminium Atom ◽  
Layer Transition ◽  
Temperature Oxidation ◽  
Gh4169 Superalloy

The aluminizing process by solid powder on the surface of GH4169 superalloy with different Y2O3content and different aluminizing temperature was investigated in this paper. The results show that the crystalline phase of aluminized coating is composed of AlNi, FeNi and AlNi3, and the phase of AlNi reaches 78.1%, which indicates that aluminium atom has infiltrated into the alloy surface. Y2O3can greatly improve compactness of the aluminized coating, increase thickness, surface micro-hardness and high temperature oxidation resistance of the aluminized coating. The thickness of the coating increases with the increase of temperature, but the microstructure of the aluminized samples cannot obviously divided into aluminized layer, transition layer and matrix when the aluminizing temperature is too high (980°C) or too low (920°C), and even the aluminized coating is porous and coarse at 980°C. The high temperature oxidation resistance of all the aluminized samples is improved compared to without aluminized samples. According to the microstructure, thickness, surface micro-hardness and high temperature oxidation resistance of aluminized coating, the optimal aluminizing process is 950°C×7h with 4%Y2O3.

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