Unanswered Questions
152 questions with no upvoted or accepted answers
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How to calculate the octahedral distortion parameters from CIF or xyz files of perovskites?
I was trying to know how to calculate the octahedral distortion parameters ($\theta_{tilt}$, $\theta_{in}$, $\theta_{out}$, $\sigma$, D) from CIF or xyz files of perovskites? Is there any example or ...
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Total energy for isolated atoms in VASP
To calculate cohesive energy, I am doing the total energy calculation for isolated atoms Fe, N, C, Mn, Ti. I have considered a large cubic system of 15A where the atom lies at the centre. N and C scf ...
- 20.1k
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wave vector and frquency dependent Dielectric function using DFT
In the following equation, $S(\omega)$ is a transmission function, $\epsilon_1$ and $\epsilon_2$ are real and imaginary dielectric functions respectively. If we notice the equation carefully, we need $...
- 935
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Two imaginary frequencies in transition state obtained by CI-NEB method
What should we do when we get two imaginary frequencies in the transition state obtained using CI-NEB? For example, I looked into the CO+O -> CO2 step on 3X3 Pt(111) with sufficient vacuum slab. ...
- 147
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Interpretation of Spin Density for FeCl₂ Monolayer Visualized in VESTA
I have performed spin density calculations for an FeCl₂ monolayer using VASP and visualized the results in VESTA. While I can see the spin density distribution, I am seeking guidance on how to ...
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How do I fill my simulation box with molecules efficiently?
I am using VASP for DFT simulations so far and want to start with AIMD of solid liquid interfaces. Now I stand before the problem of how to fill my cell appropriately with molecules. So far I have ...
- 483
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How to compute molar Gibbs free energy (chemical potential) for single molecule using gaussian09?
I want to calculate the Gibbs free energy of single gas molecule (AsH3) using Gaussian 09, but I am confused between "Thermal correction to Gibbs Free Energy" and "Sum of electronic and ...
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How to make a heterostructure
I have two hexagonal structures with lattice parameters 3.425 and 3.14. I try supercell or sqrt3 method but lattice mismatch does not reduced. Is there in way to make a heterostructure from these ...
- 383
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How to choose a proper rotation matrix and apply it to rotate unit cell about Cartesian axis to align I-Cr-I bonds parallel to Cartesian axis
I was surveying this paper Remarkably enhanced Curie temperature in monolayer CrI3 by hydrogen and oxygen adsorption: A first-principles calculations, where they have rotated the unit cell (without ...
- 24.2k
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Geometry Optimization and Symmetry (Quantum ESPRESSO)
Before asking anything, I'd like to clarify that I'm an almost a beginner in using Quantum ESPRESSO, so my question may be trivial for an advanced user.
I'd like to perform a vc-relax calculation on a ...
- 457
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Mean square displacement (MSD) graph from AIMD simulation
To get the slope from MSD graph, how to do the fitting if the graph is not perfectly linear? Do we need to do fitting only in the linear region?
- 24.2k
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Is there any tool/website available by which I can generate VASP input files?
I am familiar with QE input files, but totally new in VASP. I know by using the quantum espresso input generator(https://www.materialscloud.org/work/tools/qeinputgenerator), we can use CIF file
to get ...
- 935
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Spontaneous Polarization on a n-doped system ( ABO3 perovskite ) in VASP
I am trying to perform a spontaneous polarization calculation on a n-doped ABO3 system using the berry phase approach in VASP. I use a 3x3x3 supercell and I am trying to follow the same way we ...
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Magnetocrystalline Anisotropy Energy
How should one proceed in VASP to compute the magnetoanisotropy energy effectively?
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How to improve dielectric function calculated using Independent particle approximation VASP?
I am trying to reproduce a paper linked below. First i did scf calculation adding external electric field of 0.3V/A and than i use WAVECAR generated from there to compute frequency dependent ...
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