GW calculation for boron nitride system
Posted: Mon Aug 15, 2011 7:59 pm
I read the online instruction for VASP GW calculation, it seems that there are several steps to run the GW calculation:
1. perform a self consistent DFT run with LOPTICS = TRUE,
2. with the WAVEDER from the result of step 1 we do another calculation with ALGO = GW0, and still LOPTICS = TRUE.
3. with the CHGCAR from step 2, run a regular band calculation with ALGO = GW0.
Is my understanding correct?
However, in step 2, the calculation is stuck at the very beginning, where OUTCAR shows :
total amount of memory used by VASP on root node1536000. kBytes
========================================================================
base : 30000. kBytes
nonl-proj : 435402. kBytes
fftplans : 15229. kBytes
grid : 90210. kBytes
one-center: 421. kBytes
HF : 135. kBytes
nonlr-proj: 1947. kBytes
wavefun : 962656. kBytes
Broyden mixing: mesh for mixing (old mesh)
NGX = 41 NGY = 41 NGZ = 65
(NGX =128 NGY =128 NGZ =196)
gives a total of 109265 points
initial charge density was supplied:
charge density of overlapping atoms calculated
number of electron 216.0000000 magnetization
keeping initial charge density in first step
--------------------------------------------------------------------------------------------------------
Maximum index for augmentation-charges 851 (set IRDMAX)
--------------------------------------------------------------------------------------------------------
FEWALD: cpu time 0.01: real time 0.01
and it won't go any further.
Is it because that my unit cell is too big for this calculation. I am trying to run a 3x3 hexagonal boron nitride system which consists of 18 atoms.
Thank you
1. perform a self consistent DFT run with LOPTICS = TRUE,
2. with the WAVEDER from the result of step 1 we do another calculation with ALGO = GW0, and still LOPTICS = TRUE.
3. with the CHGCAR from step 2, run a regular band calculation with ALGO = GW0.
Is my understanding correct?
However, in step 2, the calculation is stuck at the very beginning, where OUTCAR shows :
total amount of memory used by VASP on root node1536000. kBytes
========================================================================
base : 30000. kBytes
nonl-proj : 435402. kBytes
fftplans : 15229. kBytes
grid : 90210. kBytes
one-center: 421. kBytes
HF : 135. kBytes
nonlr-proj: 1947. kBytes
wavefun : 962656. kBytes
Broyden mixing: mesh for mixing (old mesh)
NGX = 41 NGY = 41 NGZ = 65
(NGX =128 NGY =128 NGZ =196)
gives a total of 109265 points
initial charge density was supplied:
charge density of overlapping atoms calculated
number of electron 216.0000000 magnetization
keeping initial charge density in first step
--------------------------------------------------------------------------------------------------------
Maximum index for augmentation-charges 851 (set IRDMAX)
--------------------------------------------------------------------------------------------------------
FEWALD: cpu time 0.01: real time 0.01
and it won't go any further.
Is it because that my unit cell is too big for this calculation. I am trying to run a 3x3 hexagonal boron nitride system which consists of 18 atoms.
Thank you