17 Questions 19 Answers 0 Followers
Questions related from Md. Jahid Hasan Sagor
Hi, I want to calculate the magnitude of k point(in Brillouin zone) of graphene which has a hexagonal unit cell. The lattice parameters of graphene are given below: &CONTROL calculation =...
17 October 2024 7,893 3 View
I want to plot the phonon dispersion of Au. I successfully ran pw.x and ph.x. (I am sharing the input files as follows). However, while running q2r.x, I have found the error " nc already filled:...
27 September 2024 8,925 3 View
Hi, I am interested in calculation dielectric function of bulk materials. I have seen there are many ways to do that e.g, DFT epsilon.x, yambo Independent Particle: Random Phase Approximation,...
10 September 2024 372 2 View
In the attachment, $S(\omega)$ is a transmission function, $\epsilon_1$ and $\epsilon_2$ are real and imaginary dielectric functions respectively. If we notice the equation carefully, we need...
26 August 2024 4,606 3 View
Is there any post processing tools by which I can get average value of lattice parameters from cell trajectory? For example: I ran 'vc-cp' (CPMD) in quantum espresso (for Silicon) and Si.cel file...
09 July 2024 9,333 1 View
I have seen during DFT calculation some authors comment that LDA/GGA functional overestimates/underestimates the band gap/lattice constant of some materials. Before going to the main calculation,...
26 June 2024 3,513 9 View
I am trying to find out temperature dependent lattice constant (Silicon) using CPMD (NPT ensemble). If I want the lattice parameters at 300 K, should I set temp 300 K in both &cell and...
08 June 2024 4,615 0 View
Would anyone please guide me stepwise how can I find lattice parameters of a material, for example: Si, GaAs, at a finite temperature using Car-Parrinello Molecular Dynamics (CPMD)? Thank you
03 June 2024 4,401 4 View
Hi, Here is the CONTROL file of ShengBTE. ********************* &allocations nelements=2, natoms=2, ngrid(:)=12 12 12 &end &crystal...
27 May 2024 2,760 0 View
Hi, Attached here is the CIF file of CaCO3. I have opened it using Vesta and get the following data: %%%%%%%%%%% Title C Ca O3 Lattice type C Space group name Custom Space...
15 May 2024 6,633 5 View
Hi, Attached here is the CIF file of CeO2. One of the paper mentioned that they have used 192 CeO2 atoms constructed by 4*4*4 primitive cells. To generate the coordinates, I have opened it...
13 May 2024 7,976 5 View
I want to calculate the mean square displacement of GaAs using CPMD. From the mean square displacement, I want to extract the configuration of atoms (e.g atomic position of Ga and As). Could...
09 January 2024 5,212 1 View
0 I have modeled a graphene-vacuum-graphene system. Here two graphene sheets connected by L-J potential through vacuum gap (Phonon transfer through vacuum). I have simulated it considering 0.2 to...
15 October 2023 8,927 1 View
I know how to calculate dielectric function using Quantum Espresso. It gives a result at 0 K. However, in my research I need a temperature dependent dielectric function. For example, 200K, 300K...
12 September 2023 944 4 View
Hello everyone, I am doing calculations on GaAs (Quantum Espresso). I want to generate a supercell of GaAs (containing four Ga and four As). &SYSTEM celldm(1) = 10.22 ATOMIC POSITIONS...
21 June 2023 9,409 1 View
I know how to calculate dielectric constant by Quantum Espresso. But it gives the output at O K. If I want to find out the constant at room temperature, how can I do that? Can anyone explain with...
08 June 2023 2,903 1 View
How can I calculate Force Constant Matrix using DFT from First Principle? Any Guidelines? Also Which Software I may use?
02 September 2022 2,350 3 View