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11

I don't think it's ideal, but there is the term "base metal". There are various definitions for what is considered a base metal, but the main noble (or precious) metals are always excluded. Some definitions also exclude ferrous metals. Unfortunately, this variation in meaning means it might be better to just say "non-ferrous, non-noble", ...


11

For VCA, as the construction is as simple as averaging the potentials of atomic species, the main advantage is computational. This is in the sense that it is very simple to change the compositional ratio of a solid solution by just changing how you average the potentials, instead of having to work with supercells (as you would have to do with SQS or other ...


9

By making a supercell and modifying it in some way, you are creating an entirely new structure which you hope can give you some insight by being compared to the original structure. Any of the conclusions you draw from your calculations will come from the modified supercell, rather than a version where you have converted it back into the primitive cell. Some ...


6

The static energy at 0K is usually the major component of the free energy (at least for crystalline substances at moderate temperatures). So I will proceed first a search based on static energy (using USPEX or otherwise) and, then, calculate free energies for the top candidates within QHA approximation and rank them again appropriately.


5

For special quasirandom structures, the main advantage is that treating the atoms explictly allows the cell shape and ionic positions to be relaxed, capturing local atomic distortions which play a relatively large role in the electronic structure, energy and other properties. In principle, the VCA and other mean field approaches to disorder capture the same ...


5

Ionization energy is more appropriate for isolated atoms, you want the workfunction or ionization potential of your alloy surface. You calculate this usually from slab calculations because there is explicit vacuum. Work function is defined as: $$\Phi=E(vacuum)-E(Fermi)$$ If you use vasp this can be useful https://github.com/WMD-group/workfunction And a very ...


4

A few things: If you start with your supercell of pure bcc Ti, the spacegroup symmetry will be Im-3m, as expected. As soon as you replace one or a few atoms of Ti with Nb, or any different species, you are breaking symmetries and the symmetry will be lowered. Marker et al. computed elastic properties for bcc Ti-X (X=Mo,Nb,Ta,Zr,Sn) and handled the lower ...


4

Not only do I agree with the comments by TheSimpliFire, S R Maiti, and wzkchem5, that there is likely no word for this in English; I'll also go as far as to say that even the German word you suggested does not precisely fit your description of being "non-ferrous and non-noble". "Buntmetalle" just means "colorful metals". The ...


4

I have faced a similar issue and it seems that something happens while calling calculate(). I think it may be because when you use the same single equilibrium calculation for determining the Gibbs energy it does without suspending the other phase and this might be creating the problems, but I am not sure. I would suggest trying two different single ...


3

This seems to be a typo in the paper. As they mention in the introduction, austenite is the "hot" phase of this compound, so it should form on heating martensite. In their experiments, they heat samples with varying compositions to determine at what temperature the austensitic transformation starts/finishes. The martensite temperatures should ...


3

General Info As far as I understand you're taking a Fourier Transform of an image. In your case, that image corresponds to that of a microstructure alloy. So basically in 2D-Fourier transforms we are trying to model the intensity levels of the image and represent it in terms of a frequency plot. This is analogous to the 1D Fourier transform. Is there a ...


2

I managed to get the converged U$_{0.01}$Cu$_{0.99}$ potential by converging a pure Uranium potential in a Cu lattice. Then by increasing the concentration of Cu and using the old converged potential as a starting potential you can increase the concentration of Cu in steps until finally reaching a converged U$_{0.01}$Cu$_{0.99}$ potential. This is a good ...


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