Questions related to Transition Elements
Pb^2+ exist in group1 as a chloride(PbCl) with HCl as its precipitating agent while it exist in group 2 as sulphide (PbS) with H2S as its precipitating agent.
Can Pb be confirmed in both of them ?
I confirmed Pb in group 1 which made me stop half way of confirming for its presence in group 2. While we were doing the group separation for group 2, we passed it through H2S at the kipps apparatus which upon reaction with the gas turned our solution to black ppt., which we filtered to obtain a black residue which I suspect to be PbS. However for group 2 I discovered that CuS,HgS,Bi2S3 are also black in colour. Time wasn't on my side to run the confirmatory test. So is it fine to just report the one I confirmed which is group 1.
I just started to study about Mott’s Formalism and as I was going through some prerequisite material for Variable-Range Hopping Conduction I read the following paragraph,
" Theories on non-defective non-doped semiconductors show that the Fermi level is positioned around mid-gap to obey the condition of charge neutrality in the material. In the case of band conduction in SiOx this would lead to an increase in activation energy with increasing x, from around 0.9 eV in a-Si up to around 1.5 eV for suboxides with x ≈ 1.5. Indeed, an increase in activation energy has been observed in several studies on the conduction of different silicon suboxides. In these studies the x dependence of the (room temper- ature) resistivity of SiOx is easily explained in terms of an increased activation energy within a band conduction model. "
Can someone please explain how does the band gap increase when x increases in Silicon Suboxides?
PFA the document I am referring to.
Thanks in advance!
I would like to know the different ways to combine M-Se ( where M can be Cu,Co,Fe,Pd,Ru) with MXene (Ti3C2Tx). I recently happen to come across one method which is hydrothermal synthesis using autoclave, likewise are there any other different methods or is hydrothermal synthesis the only option for the given objective?
Usually, the metals are Ti, Cr, Fe, Ni; and their alloys. They do form protective films in moderate corrosive environment, and their films dissolve away in very strong corrosive environment. But why not all metal behave so? What causes their protective films to be retained?
Nickel is one of transition element,and its rarely present in diet,Nickel is a mineral. It is found in several foods including nuts, dried beans and peas, soybeans, grains, and chocolate. The body needs nickel, but in very small amounts. Nickel is a common trace element in multiple vitamins.
Nickel is used for preventing nickel levels in the blood from getting too low (nickel deficiency). It is also used for low levels of healthy red blood cells (anemia) due to iron deficiency and treating weak and brittle bones (osteoporosis), but there is no good scientific evidence to support these uses. but nowdays its found some applications,so what are other use of element?
There are three types of antiferromagnetism, namely A , C and G type. I want to perform DFT calculations with these types of antiferromagnetism using either Quantum Espresso or Wien2K codes in full inverse Heusler alloys with general formula X2YZ (X and Y being transition elements and Z being an sp element. The Xs are at (0,0,0) and (0.25,0.25,0.25), Y at (0.5,0.5,0.5) and Z at (0.75,0.750.75).
i recorded the spectrum of a transition metal complex, and get the wave length of the main characteristic absorption bands, ( at 600–620 and 500–520 nm ) , Now I need to know which absorption band is assigned for which electronic transition type ( 4T1g (F) → 4A2g (F) or 4T1g (F) → 4T2g (P) or 4T1g (F) → 4T1g (P) transitions or ........What............ )
Any suggestions how can I calculate / find that ???
Usually, when PL analysis of transition metals and it's different dericatives has been carried out, we get a PL spectrum of it having multiple peaks excited by only one (excitation) wavelengh? Why it is so? and, what is the exact role of excitation wavelength?
I want to seek the opinions of experts in the field of environmental science. I intend to determine elemental contents of some freeze dried plant samples collected after an experiment. Since I want a non destructive method of determination of these elements, mostly transition elements. I am being sceptical about the use of XRF because I have been used to the use of conventional method of total digestion and analysis by either A AS or ICP MS. So, I want to hear opinion of people that have used XRF concerning the reliability and reproducibility of results. Is it better than normal conventional element analysis and how reliable are the results from XRF? Thank you all
Hello all, could you tell me any chemicals that has similar reaction properties to Zero Valent Iron (ZVI) Fe0. it is transition element. and very reactive chemical ( catalyst. Thanks
i am think if i shall do comparative studies for environmental remediation and addictive in process engineering.
Can anybody tell me why there is a strong satellite peaks in photoelectron spectroscopy for transition and rare earth elements having unpaired number of electrons. But it does not observe for closed shell structure. As an example Cu+1 (d10) configuration does not have satellite peaks and Cu+2 (d9) having a strong satellite peaks.
How do I separate ions of transition metals: nickel, cobalt and manganese by precipitation (hydroxide and carbonate) from the leaching solution?
Has anyone the experience about the charge ordered system? e.g. La1-xSrxMnO3 or RNiO3 systems. For the long range order type, the MR~H curve will be symmetrical?
I am trying to optimize a transition state where there is two different bond breaking events. It is a proton transfer reaction and a concerted mechanism. I have modeled a couple of transition states but none of them seems to give me the correct TS. I do not see any bond breaking/forming in any of the transition states I have modeled . Can anyone help me or give me some feedback?