Continous timeout for Phonon Calculation (Hessian Matrix and Dielectric function)
Posted: Thu Mar 07, 2024 10:10 pm
Hi all,
My goal is to model the refractive index in Terahertz and infrared ranges for a few organic crystals, thus I would to calculate the hessian matrix and the dielectric function with VASP. So, I submitted a job with IBRION = 6 (I also have my setup parameters in the end). However the calculation kept being timeout due to the wall time limit (50hrs) of the supercomputer that I use, and I have been resubmitting it again and again with an existing WAVECAR for 4 times now. I am just wondering if this kind of calculation to get hessian matric and dielectric function indeed takes so long or I am not restarting it correctly. I also see a comment in ResearchGate forum saying that this type of calculation could not be restarted, is it the case? (Bogdanovski, Dimitri. (2020). Re: Restart VASP job with IBRION=6?. Retrieved from: https://www.researchgate.net/post/Resta ... n/download.)
Below are my calculation steps:
I first converted a cif file to a POSCAR file with VESTA by outputting the current unit cell. Then I performed 4 consecutive relaxations (IBRION = 2) until the external pressure is below 1kb. After that, I submitted the job to calculate the hessian matrix and dielectric function with k-point mesh of 3x3x3 and with the below setup:
ISYM = 0
PREC = Accurate
ENCUT = 400
ISIF = 7
IBRION = 6
EDIFFG = -0.0001
IALGO = 38
NFREE = 2
POTIM = 0.015
ISMEAR = 0;
SIGMA = 0.1
GGA = PS
LEPSILON = .TRUE.
NCORE = 2
NSIM = 4
LREAL = Auto
LOPTICS = .TRUE.
I would appreciate any feedbacks or suggestions, thanks.
My goal is to model the refractive index in Terahertz and infrared ranges for a few organic crystals, thus I would to calculate the hessian matrix and the dielectric function with VASP. So, I submitted a job with IBRION = 6 (I also have my setup parameters in the end). However the calculation kept being timeout due to the wall time limit (50hrs) of the supercomputer that I use, and I have been resubmitting it again and again with an existing WAVECAR for 4 times now. I am just wondering if this kind of calculation to get hessian matric and dielectric function indeed takes so long or I am not restarting it correctly. I also see a comment in ResearchGate forum saying that this type of calculation could not be restarted, is it the case? (Bogdanovski, Dimitri. (2020). Re: Restart VASP job with IBRION=6?. Retrieved from: https://www.researchgate.net/post/Resta ... n/download.)
Below are my calculation steps:
I first converted a cif file to a POSCAR file with VESTA by outputting the current unit cell. Then I performed 4 consecutive relaxations (IBRION = 2) until the external pressure is below 1kb. After that, I submitted the job to calculate the hessian matrix and dielectric function with k-point mesh of 3x3x3 and with the below setup:
ISYM = 0
PREC = Accurate
ENCUT = 400
ISIF = 7
IBRION = 6
EDIFFG = -0.0001
IALGO = 38
NFREE = 2
POTIM = 0.015
ISMEAR = 0;
SIGMA = 0.1
GGA = PS
LEPSILON = .TRUE.
NCORE = 2
NSIM = 4
LREAL = Auto
LOPTICS = .TRUE.
I would appreciate any feedbacks or suggestions, thanks.