Robert Appleton

7 Questions 10 Answers 0 Followers

Questions related from Robert Appleton

Why does VASP not write the pair correlation function for energy minimization?

In the documentation, VASP says the averaged pair correlation function is written to the PCDAT file for IBRION >= 0. When I run MD (IBRION = 0) the pair correlation function is written to the...

15 October 2021 9,381 0 View

How to get phonon mean free path?

I have used a combination of VASP, Phonopy and ShengBTE to get the second order and third order force constants, born effective charges, and then thermal conductivity amongst other quantities from...

15 May 2021 5,464 5 View

How to fix born effective charge calculation in vasp?

I am studying the phonons of the hexagonal GST (Ge2Sb2Te5) system. I used vasp to optimize the structure and then phonopy to generate the displacements. Using vasp to calculate the forces and then...

18 April 2021 9,416 1 View

How much does radiative heat transfer effect thermal conductivity of materials and how to compare calculations to experirment?

I am calculating the phonon contribution to thermal conductivity for 4 perovskites (BaZrO3, BaSnO3, BaHfO3, and KTaO3) with relatively wide bandgap. When I compare my results for BaZrO3 to the...

28 December 2020 3,462 3 View

Anyone familiar with this error in VASP?

I am calculating force sets on finite displacements generated by phonopy. My structure is TlNbO3 and phonopy generates 3 displacement poscars. When I used a 2x2x2 supercell and calculated the...

21 October 2019 8,206 12 View

Unable to converge k-mesh with respect to total energy. Any suggestions on how to proceed?

I am trying to do k point convergence test and I am getting the following plot for total energy vs increasing the size of the k mesh. I guess brute force would suggest to continue to increase the...

03 September 2019 5,281 2 View

VASP strucutrual optimization what comes first, Volume relaxation and k-point converegence?

I want to study a material and first I need to optimize the structure with vasp. I know I need to relax the volume and I know I should do convergence analysis by plotting total energy vs k-points....

20 August 2019 1,987 10 View