Two new quaternary copper bismuth sulfide halides: CuBi2S3Cl and CuBi2S3Br as candidates for copper ion conductivity

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Ina Remy-Speckmann ◽  
Thomas Bredow ◽  
Martin Lerch

Abstract Two new copper bismuth sulfide halides, CuBi2S3Cl and CuBi2S3Br, were synthesized by a two-step process of ball milling followed by annealing. Both compounds are obtained as dark grey powders and crystallize in the monoclinic space group C2/m with lattice parameters a = 12.9458(11) Å, b = 3.9845(3) Å, c = 9.1024(8) Å and β = 91.150(3)° for the sulfide chloride and a = 13.3498(8) Å, b = 4.1092(2) Å, c = 9.4173(6) Å and β = 90.322(4)° for the sulfide bromide. Also known for related compounds, the copper atoms are strongly disordered. Quantum-chemical calculations suggest that modelling the structure with fixed copper positions does not satisfactorily describe all structural features, which insinuates copper ion mobility at elevated temperatures.

2021 ◽  
Vol 13 (1) ◽  
Author(s):  
A. M. Ayuba ◽  
◽  
M. Abubakar ◽  

The present work describes the computational methods for the corrosion inhibition of aluminium using three selected chemical constituents (5-methyldihydroflavasperone, 5-methylflavasperone and methoxylated naphthyl butanone) reportedly obtained from the leaves extract of Guirea senegalensis. Quantum chemical calculations including EHOMO, ELUMO, energy gap (ΔE), electronegativity (χ), global hardness (η) and fraction of electrons transfer from the inhibitor molecule to the aluminium surface (ΔN) were calculated. The local reactive sites through Fukui indices which explain the effect of structural features of these components in relation to electrophilic and nucleophilic point of attack were evaluated. The similarities in quantum chemical parameters for the compounds obtained revealed that the adsorption strengths of the molecules will be mostly determined by molecular size rather than electronic structure parameters. Fukui indices showed that the point of interaction of inhibitor molecule with the Al(l10) surface were through aromatic carbon atom rich in pi-electrons and oxygen atom of the alkanone functional group in the inhibitor molecules. Molecular dynamics simulations describing the adsorption behavior of the inhibitor molecule on Al(110) surface through Forcite quench molecular dynamics were carried out. The compounds were found to all obey the mechanism of physical adsorption because of their relatively low adsorption energies.


ChemInform ◽  
2006 ◽  
Vol 37 (40) ◽  
Author(s):  
Francesco Caruso ◽  
Miriam Rossi ◽  
Cristian Opazo ◽  
Claudio Pettinari

2004 ◽  
Vol 59 (8) ◽  
pp. 869-876 ◽  
Author(s):  
L. Engelke ◽  
R. Stähler ◽  
M. Schur ◽  
C. Näther ◽  
W. Bensch ◽  
...  

AbstractThe two new compounds Mn2(L)Sb2S5 (L = diethylenetriamine = DIEN, N-methyl-1,3- diaminopropane = MDAP) were prepared under solvothermal conditions using the elements as starting materials. Both compounds crystallise in the monoclinic space group P21/c with the lattice parameters a=10.669(7), b=12.805(2), c=12.072(1)Å , β =115.786(7)°,V =1485.1(4) Å3 for L = DIEN and a = 10.1859(7), b = 12.7806(6), c = 12.1256(8)Å , β = 110.173(8)°, V = 1481.7(2) Å3 for L = MDAP and Z = 4. The primary building units are SbS3 pyramids, MnS6 and MnS4N2 distorted octahedra. These primary building blocks are interconnected to form Mn2Sb2S4 hetero-cubane units. The hetero-cubanes share common corners, edges and faces thus forming a second heterocubane. These secondary building units are joined to form layers within the (100) plane. The connection mode yields ellipsoidal pores within the layers. The amines are exclusively bound to one of the two crystallographically independent Mn2+ cations and they point into the pores and between the layers separating the layers from each other. The interlayer separation and the size of the pores depend on the sterical requirements of the amine incorporated into the network. A pronounced distortion of the MnS4N2 octahedron results from a significant elongation of one Mn-S distance from 2.866 Å (L = methylamine, MA) to 3.185 Å for L = MDAP. The magnetic susceptibility curves are typical for low-dimensional antiferromagnetic materials and the large negative values for the Weiss constant Θ indicate strong antiferromagnetic exchange interactions. The magnetic properties are significantly influenced by the change of the Mn-S bonds introduced by the different amines. The compounds decompose at elevated temperatures with a two step reaction for L = MA and ethylenediamine and in a one step reaction for the bidentate acting amine molecules.


2012 ◽  
Vol 56 (6) ◽  
pp. 3207-3215 ◽  
Author(s):  
Katrin Ingram ◽  
William Ellis ◽  
Jennifer Keiser

ABSTRACTInteresting antischistosomal properties have been documented for the antimalarial mefloquine, a 4-quinolinemethanol. We evaluated the antischistosomal activities of nine mefloquine-related compounds belonging to the 4-pyridinemethanols, 9-phenanthrenmethanols, and 4-quinolinemethanols. Eight compounds revealed high activities againstSchistosoma mansoni in vitro, with two drugs (the 4-quinolinemethanols WR7573 and WR7930) characterized by significantly lower half-maximal inhibitory concentrations (IC50s) (2.7 and 3.5 μM, respectively) compared to mefloquine (11.4 μM). Mefloquine and WR7930 showed significantly decreased IC50s when incubated in the presence of hemoglobin. High worm burden reductions (WBR) were obtained with enpiroline (WBR, 82.7%; dosage, 200 mg/kg of body weight) and itsthreoisomers (+)-threo(WBR, 100%) and (−)-threo(WBR, 89%) and with WR7930 (WBR, 87%; dosage, 100 mg/kg) against adultS. mansoniin mice. Furthermore, excellentin vitroandin vivoantischistosomal activity was observed for two WR7930-related structures (WR29252 and WR7524). In addition, mefloquine (WBR, 81%), enpiroline (WBR, 77%), and WR7930 (WBR, 100%) showed high activities againstS. haematobiumharbored in mice following single oral doses of 200 mg/kg. These results provide a deeper insight into the structural features of the arylmethanols that rule antischistosomal activity. Further studies should be launched with enpiroline and WR7930.


2017 ◽  
Vol 72 (2) ◽  
pp. 95-99 ◽  
Author(s):  
Yang Chi ◽  
Yan Zhuang ◽  
Sheng-Ping Guo

AbstractThe synthesis and crystal structure of the rare earth borogermanate EuGeBO5 are reported. It is synthesized by high-temperature solid-state reaction and crystallizes in the monoclinic space group P21/c (no. 14) with the unit cell parameters a=4.8860(5), b=7.5229(8), c=9.9587(10) Å, and β=91.709(3)°. Its crystal structure features a polyanion-type layer (GeBO5)3− constructed by BO4 and GeO4 tetrahedra connected alternatingly. Eu3+ ions are located in cavities and are coordinated by eight O atoms. Various structures of the related compounds REMM′O5 (RE=rare earth metal; M=Si, Ge, and Sn; M′=B, Al, and Ga) are also discussed.


1966 ◽  
Vol 46 (3) ◽  
pp. 303-305 ◽  
Author(s):  
Leonard C Harber ◽  
Harriet Harris ◽  
Rudolf L Baer

1999 ◽  
Vol 604 ◽  
Author(s):  
H. Fritze ◽  
H. L. Tuller ◽  
G. Borchardt ◽  
T. Fukuda

AbstractMaterials such as langasite (La3Ga5SiO14) and related compounds are promising candidates for piezoelectric applications at high temperatures. In particular, langasite does not exhibit phase transformations up to the melting point of 1470 °C. Langasite was investigated with respect to potential applications in high temperature resonator devices. In contrast to current resonator materials, we have observed bulk oscillations at temperatures of up to 750 °C in langasite devices. At 700 °C the mass load response for 0.78 mm thick resonators is approximately 0.10 µg/Hz.At elevated temperatures, the bulk resistivity of the resonator devices cannot be neglected due to attenuation of the resonance signal. Therefore, the temperature dependence of the electrical properties of langasite resonator devices, including bulk resistivity, capacity and resonance frequency were measured and are presented. The electrical conductivity is characterized by an activation energy of 105 kJ/mol. In order to confirm langasites stability with respect to oxidation-reduction reactions, we examined the oxygen diffusivity by measuring 18O tracer profiles by SIMS. The diffusivity along the Y-axis is given by D = 5-10−5 exp(-140 kJ/mol / RT) cm2/s in the temperature range from 500 to 800 °C. Langasite shows low oxygen diffusion coefficients with respect to other materials which might be investigated using a langasite microbalance. This would, for example, enable oxygen diffusion kinetics to be examined in YBa2Cu3O6 at 600 °C by means of 18O/16O exchange.


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