16 votes

How to understand the spin of exciton?

As you mentioned in the question, excitons are indeed bound electron-hole pairs. They are often considered to be the signature of optical spectra in insulating solids. Adding onto the comment by tmph, ...
user avatar
  • 2,212
11 votes
Accepted

Quantum Dot properties using VASP

Calculation of QD using VASP is not that much different from bulk calculations; you just need to ensure that sufficient vacuum is applied in all 3 spatial dimensions. My experience is that 10-15 ...
user avatar
  • 391
9 votes
Accepted

Can deformation potential theory be applied to 2D and 1D systems?

Deformation potential theory is almost always used to study 2D materials. The first line of the abstract of the original Bardeen-Shockley paper mentions "deformations of the crystal lattice"....
user avatar
  • 28.6k
9 votes

How to understand the spin of exciton?

First I mention this very similar question on Physics SE and the related answer. Then, a couple of points which are not well addressed in the previous answer in my opinion. First of all we are here ...
user avatar
9 votes

How can I know if 3D aperiodic systems are not interacting with each other using Quantum ESPRESSO?

Since QE is a planewave based code and we are talking about cells, its important to realize its periodic so its always interacting with itself to some degree. The only way to check if its ...
user avatar
6 votes

Quantum Dot properties using VASP

It is worthwhile to add to liuyun's answer that even though these calculations are in theory straightforward there are some caveats you have to acknowledge. Band gap tends to be underestimated by ...
user avatar
6 votes

Geometrical Optimization not converging for a double perovskite quantum dot, using Gaussian

OK, I do not want to be that guy, but I will be that guy. Some general remarks You should plan better your calculation projects. You got 129 SCF cycle calculated in about 3 days. Even if this ...
user avatar
  • 1,648
5 votes

Geometrical Optimization not converging, where am I going wrong?

Where was I going wrong- the quantum dot structure was not neutral. Thanks to @AnoopANair, I was able to find the problem. For anyone having a similar problem look at this video - https://www.youtube....
user avatar
5 votes

Geometrical Optimization not converging for a double perovskite quantum dot, using Gaussian

I didn't deal with perovskite before, but I got this problem when I used metal atom in my complex. So, from my point of view, I think your calculation needs more cycles to get converged so what about ...
user avatar
5 votes
Accepted

SCF Calculation not converging after two decimal places in Quantum ESPRESSO

My suggestion is that you first get an SCF calculation to converge for this structure before you try relaxing, especially if you aren't sure what you're going to get. Then you can proceed to ...
user avatar
2 votes

Error while doing a band structure calculation in Quantum ESPRESSO

This may not be the issue, but the manual says the max_seconds keyword under &control is maximum CPU time, not wall time, ...

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