Xn:Harmful;12018-22-3Relevant articles and documents
Rzymkowski, J.
, p. 610 - 610 (1935)
Electronic structure of Cr1-δS (δ=0, 0.17) with NiAs-type crystal structure
Koyama,Sato,Ueda,Hirai,Taniguchi
, p. 243 - 246 (2003)
Valence-band and conduction-band the electronic structure of the CrS (δ=0) and Cr5S6 (δ=0.17) has been investigated by means of photoemission and inverse-photoemission spectroscopies. The bandwidth of the valence bands of Cr5S6 (8.5 eV) is wider than that of CrS (8.1 eV), though the Cr 3d partial density of states evaluated from the Cr 3p-3d resonant photoemission spectroscopy is almost unchanged between the two compounds concerning shapes as well as binding energies. The Cr 3d (t2g) exchange splitting energies of CrS and Cr5S6 are determined to be 3.9 and 3.3 eV, respectively.
Synthesis and characterization of 3-methyl-5-oxo-N,1-diphenyl-4,5-dihydro-1-H-pyrazole-4-carbothioamide and its metal complexes
El-Shazly
, p. 259 - 264 (2009)
The molecular parameters have been calculated to confirm the geometry of 3-methyl-5-oxo-N,1-diphenyl-4,5-dihydro-1-H-pyrazole-4-carbothioamide, HL. The compound is introduced as a new chelating agent for complexation with Cr(III), Fe(III), Co(II), Ni(II) and Cu(II) ions. The isolated chelates were characterized by partial elemental analyses, magnetic moments, spectra (IR, UV-vis, ESR; 1H NMR) and thermal studies. The protonation constant of HL (5.04) and the stepwise stability constants of its Co(II), Cu(II), Cr(III) and Fe(III) complexes were calculated. The ligand coordinates as a monobasic bidentate through hydroxo and thiol groups in all complexes except Cr(III) which acts as a monobasic monodentate through the enolized carbonyl oxygen. Cr(III) and Fe(III) complexes measured normal magnetic moments; Cu(II) and Co(II) measured subnormal while Ni(II) complex is diamagnetic. The data confirm a high spin and low spin octahedral structures for the Fe(III) and Co(II) complexes. The ESR spectrum of the Cu(II) complex support the binuclear structure. The molecular parameters have also been calculated for the Cu(II) and Fe(III) complexes. The thermal decomposition stages of the complexes confirm the MS to be the residual part. Also, the thermodynamic and kinetic parameters were calculated for some decomposition steps.
Microwave-assisted Solid-state Reactions involving Metal Powders
Whittaker, A. Gavin,Mingos, D. Michael P.
, p. 2073 - 2080 (1995)
The ability of metal powders to couple to microwave radiation at 2450 MHz has been used to accelerate a range of solid-state reactions.Although metal objects cause extensive arcing within a microwave cavity, metal powders couple in a more conventional manner with the microwave radiation and experience high heating rates.This property has been utilised for the synthesis of metal chalcogenides and metal cluster compounds of the Group 5 and 6 elements.
High-temperature interactions of transition-metal carbides with Na2SO4
Mobin, M.,Malik, A. U.
, p. 243 - 254 (1991)
The high-temperature (900-1200 K) interaction of transition-metal carbides namely Cr7C3, Fe3C, TiC, ZrC, NbC, TaC, MoC, WC, VC and HfC with Na2SO4 has been studied in a stream of pure and dried oxygen gas. Thermogravimetric studies were carried out by measuring the weight change as a function of time and mole fraction of Na2SO4 in the reaction mixture. The presence of different constituents in the reaction products were identified by X-ray diffraction analysis and the morphologies of the reaction products were discussed on the basis of metallography, scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDAX). The quantitative determination of soluble metal species in the aqueous solutions of Na2SO4-transition-metal carbide products was carried out by atomic absorption spectroscopy. At high temperatures, transition-metal carbides interact with Na2SO4, forming metal oxides. The resulting metal oxide interacts with Na2SO4 forming a soluble sodium metal oxide or a metal sulphide depending upon the local condition prevailing during the reaction.
