Unanswered Questions
55 questions with no upvoted or accepted answers
22
votes
0
answers
248
views
Is there a software that can do derivatives with respect to user defined vibrational modes?
I'm doing some property calculations that depend on a sum of derivatives of some quantity with respect to normal vibrational modes. I was hoping to find some physical intuition relating the type of ...
- 15.9k
9
votes
0
answers
184
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How to do parity analysis of band extrema?
To check whether electronic transitions are allowed between valence band maximum (VBM) and conduction band minimum (CBM) as per Laporte's rule, the parity of VBM/CBM is needed to be known. This paper ...
- 939
7
votes
0
answers
46
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How to determine if hybridization takes place between orbitals in an ab initio calculation using Quantum ESPRESSO?
I'm using Quantum ESPRESSO to determine the electronic properties of systems. Now I want to confirm if hybridization takes place between orbitals. I have generated density of states and projected ...
6
votes
0
answers
105
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What are the parameters in PySCF's Selected Configuration Interaction code
Dear StackExchange Members,
I'm using the native PySCF implementation of selected configuration interaction (SCI). However, I can't seem to find any documentation detailing the algorithm or various ...
- 20.1k
6
votes
0
answers
77
views
Benchmarking DFT vs Experimental Gaps - Confusion over Fundamental and Optical Gaps
Recently, I've come across discussions about the differences between fundamental (or electronic) bandgaps and optical bandgaps, with the two quantities differing mainly by the electron-hole binding ...
- 1,366
5
votes
0
answers
41
views
Rich editing of ASE images
I want to produce some images related to graphene-like materials.
I was able to draw them using ASE visualize module after constructing the atomistic model. However ...
- 24.2k
5
votes
0
answers
77
views
Can the electron charge density of two material systems be similar?
Broadly given two electron charge density (ECD) fields, is it possible to distinguish between the elements present in both the systems?
Since the ECD does not explicitly present any information on the ...
- 3,770
5
votes
0
answers
163
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Actual calculation of Coulomb energy in DFT softwares
I have a question about the actual calculation of classical Coulomb interaction term in density functional theory (DFT) softwares.
Of course I understand the form Coulomb energy as:
$\int\int \frac{\...
- 1,799
4
votes
0
answers
27
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Understanding Oxidation States and Magnetic Moments in Multivalent Transition Metal Oxides
I’m reading some papers on using density functional theory (DFT) to study oxidation states in multivalent transition metal oxides, but I’m having difficulty interpreting the oxidation-state ...
4
votes
0
answers
44
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What software is fit for calculating an atomic and electronic structure of a newly formed nanocluster after injecting impurities into an initial one?
Let's suppose there is a nanocluster and its structrure is known. The problem is to inject impurities into this nanocluster. The impurities can be injected in different quantitites but consist only of ...
- 1,027
4
votes
1
answer
142
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How to use rigid scan with dummy atoms in gaussian?
I am trying to use rigid scan using gaussian 09. In my case, there are three water molecules and I have placed a dummy atom at the centroid of the three water molecules. For simplicity, I want to ...
CommunityBot
- 1
4
votes
0
answers
28
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bandstructure calculation of two-dimensional ferrovalley (RuClBr) in quantum espresso
We try to calculate bandstructure of single layer RuClBr reported in fig.4 of 'https://pubs.rsc.org/en/content/articlelanding/2016/pq/d3nr00346a/unauth'. But our obtained bandstructure is not similar ...
4
votes
0
answers
77
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Solvation_analysis subpackage for MDAnalysis multi-atom solute
I have a simulation trajectory from DFTB+ for 1 NaNO3 in 32 H2O molecules. The trajectory is in xyz format and I converted a frame of xyz to pdb using openbabel to serve as topology input.
I am ...
4
votes
0
answers
46
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Which one of the following showing the correct structure Jsmol or Vesta? Or they are just same
Let me explain. I found that the structure for TiFeSi given in the ICSD database using Jsmol software is a little different from what can be obtained using Vesta software using the same cif file ...
3
votes
0
answers
19
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NaN result using ShengBTE
I tried using ShengBTE t get the thermal conductivity of PE after performing phonon calculations using quantum espresso. When I used version 1.5.0 ShengBTE I got some numbers at the beginning of the ...
- 31