# Tag Info

10

Plasticity is still an actively researched area. The Ludwik-Hollomon equation is one model that is used for the strain-hardening region since it captures the convex shape of the curve using a power law: $$\sigma = K \epsilon^{n} \tag{1}$$ Here, $n$ is known as the strain hardening coefficient or strain hardening exponent. This equation only captures the ...

10

Structural: You should investigate the stability of your structure. In detail, you should verify: Dynamical stability: phonon spectrum. Thermal stability: molecular dynamics (MD) simulations Mechanical stability: elastic constants $\Rightarrow$ Born criteria Electronic: Band structure and density of states calculations. Maybe you should compare the ...

9

I'm not sure if this will exactly answer your question because dashboard is loosely defined, but I find "networks" to be a great way to represent reaction data. For example, Rxn4Chemistry categorizes reactions in a way that "would be too large or complex to be simply visualized in a small number of plots." https://rxn4chemistry.github.io/...

8

The error of a MD simulation can be roughly partitioned into four contributions: Error due to short-period statistical fluctuations; Error due to poor- or non-ergodicity (in other words, extremely long-period statistical fluctuations); Error due to numerical round-off and the use of a finite time step; Error due to the force field itself. Quantification of ...

8

You can find a list of what you are looking for, in this link attached. Most of them have experimental properties of molecular materials. I have shared a few examples below: Edited: The PDBbind database is designed to provide a collection of experimentally measured binding affinity data (Kd, Ki, and IC50) exclusively for the protein-ligand complexes ...

7

First of all make sure both phases are stable or not, to check stability of any phase, find mechanical stability and dynamical stability. From mechanical stability, I am referring to stiffness matrix should be positive definite, and dynamical stability means no imaginary vibration frequency exists. Compare stability of two phases Basically you need to find ...

6

One of the papers citing the paper you linked is this paper : G. Murrieta, A. Tapia, and R. de Coss, Structural stability of carbon in the face-centered-cubic (Fm$\bar{3}$m) phase, Carbon 4, 771-774 (2004). It concludes with: "In order to evaluate the structural stability of the fcc phase of carbon, we have calculated the total energy as a function of ...

5

A useful reference for this is [1], which describes how to compute the energy, forces, and stress tensor efficiently when performing PBC calculations using Gaussian atomic orbitals. Assuming you can calculate forces, the stress isn't too much more challenging to calculate. For a uniform lattice deformation due to strain $\epsilon_{ab}$, the stress is ...

5

This answer is partly based on the Computational Materials Physics Course by Stefaan Cottenier. Follow the steps provided below: Prepare a text file with two columns, the first column being the unit cell volume (a.u^3 or Å^3) of each of your calculations, the second column being the corresponding total energy (Ry). Type ev.x in the terminal, which will ask ...

5

I know it's a boring thing to say, but: It depends on what you want to do. The way I use Langevin thermostats, is to ensure good equipartitioning in my setup, so that I don't have any local hotspots in the system or something like that. If heat transfer is slow in the system, "global" thermostats like Nosé-Hoover and the like will equilibrate ...

5

The other answer is great and comes from a viewpoint of macroscopic plasticity. I'd just like to note that another perspective on plasticity exists, a multiscale view based on following atomistic mechanisms up through the length scales to aim for an understanding of plasticity that is increasingly based on physical mechanisms. The enormous range of length ...

4

I gave it another try myself. In terms of databases/datasets, the best resource I found was the List of chemical databases in Wikipedia. Within that rather extensive list list, in terms of actual dashboards (which allow to analyse and display the results rather than merely browsing collections of data) these are the two best examples I found: The vast ...

4

The values that you quoted for the densities in the liquid and solid phases, were most likely obtained from experiments, in the following very simple way: (1) take exactly 1 liter of the substance (2) measure it's mass in grams (3) the density in units of g/L is simply the result of the measurement in step (2) (4) divide the result in step (3) by 1000 to ...

4

Unlike other properties of matter such as electrical conductivity and heat capacity, which can be defined quite precisely, flammability is more like "hardness" which is more vaguely defined (for example using Mohs hardness scale). The flammability of a substance may seem to be categorized rather arbitrarily, for example the HMIS (Hazardous ...

3

Elastic constants can be calculated using two approach, one with Energy-strain relationship and another with stress-strain relationship. The key ingredient in above two methods is energy or stress at particular mode of distortion. For example in cubic crystal which have 3 fold symmetry about body diagonal need three independent elastic parameters to define ...

3

There has indeed been quite a lot of research in this area, as is readily uncovered by searching for "improving the strength of graphene" in your search engine of choice; for example, this 2017 review https://www.sciencedirect.com/science/article/pii/S0079642517300968. Graphene is often highlighted as having high mechanical strength, but this ...

3

Some years ago I found the following steps in ResearchGate: You need: QuantumEspresso (QE) Phono3py ShengBTE & thirdorder.py First, you need to create a QE input file (pwscf), using ibrav=0, lattice vectors in bohr units, atomic coordinates in crystal units. Using the input file, run phono3py/third_order.py to create supercell within finite ...

2

Lead in lead crystal has the effect of making the glass glossy in finish. A lead crystal decanter could have a smoother surface than lead-free glass, which is more resistant to liquid and so the liquid flows away more readily. The addition of lead also provides an improved look to the finished product through increasing the refractive index and density of ...

2

I got the answer to this question on the GROMACS forum which can be found here. the thermostat influence in the non-equilibrium cosine perturbation approach is automatically taken care by GROMACS, which biases termperature rescaling based on the velocity profile of fluid particles. However, some thermostats will introduce additional ‘artificial’ viscosity, ...

Only top voted, non community-wiki answers of a minimum length are eligible