UT theoretical chemistry code forum

HI All,
I'm N D Senthil Ram, I'm working on MXene with DFT in VASP, I'm to start NEB calculation for MXene to figure out the pathways for the catalytic conversion of gases using MXene. I am pleased by the post and support in this forum, and I would request if anyone can share your thought for starting NEB calculation for my MXene I'm working on, it would be of great support to me

Thank you in advance

NOw I tied to set NEB, I get the following error...

Can't locate Vasp.pm in @INC (@INC contains: /opt/home/senthil_ram/bin /opt/home/senthil_ram/perl5/lib/perl5 /usr/local/lib64/perl5 /usr/local/share/perl5 /usr/lib64/perl5/vendor_perl /usr/share/perl5/vendor_perl /usr/lib64/perl5 /usr/share/perl5 .) at /opt/home/senthil_ram/bin/nebmake.pl line 8.
BEGIN failed--compilation aborted at /opt/home/senthil_ram/bin/nebmake.pl line 8.

Yeah! finally I got it worked...


nebmake.pl POSCAR.IS POSCAR.FS 5
filetype1: vasp5
filetype2: vasp5

OK, ALL SETUP HERE
FOR LATER ANALYSIS, PUT OUTCARs IN FOLDERS 00 and 06 !!!

Coming on to the INCAR file, can anyone suggest me if this is ok?

PREC = Accurate
ENCUT = 600
ALGO = All
ISMEAR = 0
SIGMA = 0.01

# parallelization
LPLANE = .TRUE. # distribute real-space mesh
NPAR = 8 # number of cores per computing node
LORBIT = 11
LREAL=.AUTO.
IALGO = 38
#NELECT = 50 #7*nions+1
# ISPIN = 2
# MAGMOM = 4*0

# relax
ISIF = 3 # 2=atoms, 3=2+lattice, 4=shape+ions
NFREE = 20
NELMIN = 4 # minimum number of electronic steps
NELM = 150
EDIFF = 1E-6 # SCF energy convergence 1E-7
EDIFFG = -0.03 # max force for ionic steps -0.01
NSW = 250 # max ionic steps
NUPDOWN = 0

# outputs
NWRITE = 1 # {0|1|2} default:1
LCHARG = .FALSE.
LWAVE = .FALSE.
LAECHG = .FALSE.
ISTART = 0
ICHARG = 2
IMAGES = 5 # Number of NEB images between the fixed endpoints
SPRING = -5.0 # The spring constant, in eV/Ang^2 between the images; negative value turns on nudging
ICHAIN = 0 # Indicates which method to run. NEB (ICHAIN=0) is the default
LCLIMB = .TRUE. # Flag to turn on the climbing image algorithm
IBRION = 3 # Disbale VASP default optimizers which are basesd on Energy
LNEBCELL = .TRUE. # Flag to turn on SS-NEB. Used with ISIF=3 and IOPT=3
POTIM = 0 # Disbale VASP default optimizers which are basesd on Energy
IOPT = 3 # QM (Quick-Min) force based optimizers is used and good for high force far from minmum
#MAXMOVE = 0.2 # Maximum allowed step size for translation(Default comes with IOPT=3)
TIMESTEP = 0.1 # Dynamical time step (Default comes with IOPT=3)
LSCALAPACK = .FALSE.

I would always recommend using cheap setting for the initial convergence of an NEB, including normal precision, a cutoff closer to 400 eV and a minimal KPOINT mesh. Once you have a converged path, it is easy to increase precision. But also, why ALGO=All? Anyway, I can't really tell more without seeing the specific system an initial geometry of the path.

Hi Graeme,
I appreciate your interest and response to all of our interested parties. THank you. By the way my system is Pristine structure based MXene
This is my system
Ti2CO2_CO2
1.0
9.2114000320 0.0000000000 0.0000000000
-4.6057000160 7.9773064322 0.0000000000
0.0000000000 0.0000000000 36.9723014832
C O Ti
10 20 18
Cartesian
1.545442550 2.670243776 18.607049074
4.624906062 2.651098155 18.604091680
-1.496253722 2.631154908 18.604461905
-0.010869389 5.327564359 18.610008671
3.070942788 5.312487221 18.607049074
6.152754417 5.297410082 18.604091680
3.032439051 0.016513024 18.609638446
1.516979515 7.973876287 18.610008671
4.596442615 7.954730427 18.607049074
1.954382652 3.844264022 14.764148787
-0.021969170 1.779976405 20.781021942
1.558154319 0.867691604 16.433078409
3.064494493 1.771201338 20.788045200
4.606390677 0.888592180 16.436406028
6.141286572 1.759075889 20.777694323
7.683090825 0.876466671 16.426054049
-1.527941006 4.430197172 20.777694323
0.007323125 3.536260130 16.426054049
1.540836772 4.422219968 20.778802795
3.065001053 3.542243152 16.435297556
4.618181393 4.419188279 20.782870864
6.141009992 3.539929682 16.433078409
-3.076791804 7.088634430 20.788045200
-1.541527742 6.194697388 16.436406028
0.000829054 7.084965116 20.781021942
1.523703635 6.205786163 16.431230589
3.076883974 7.082731290 20.778802795
4.601048530 6.202754473 16.435297556
0.780343697 3.765368302 14.764148787
3.128375900 3.923239385 14.764148787
-0.052366755 1.797526420 17.320783465
1.588552007 0.850141530 19.893316887
3.032208683 1.762506034 17.315237801
4.649638459 0.871440978 19.896644505
6.097946551 1.776227091 17.317455846
7.715376395 0.885161916 19.898861448
-1.564464118 4.459154655 17.317455846
0.015935676 3.503952146 19.898861448
1.526743682 4.418550179 17.307474092
3.068870154 3.528203045 19.906627361
4.591652496 4.434505062 17.315237801
6.142345812 3.539211700 19.914391069
-3.085450680 7.121022534 17.315237801
-1.505050749 6.165819787 19.896644505
-0.000460372 7.085762504 17.299709282
1.550232532 6.190469380 19.898861448
3.073014874 7.096771397 17.307474092
4.615141895 6.206424263 19.906627361

I'm using IALGO=38 for, but not sure to use ALGO+Normal, so used ALL
I'm a novice to start on MXene DFT

This is my VASPRUN.XML

if you run into any problems or want advice, the best thing is to tar/gz the entire calculation (without CHG* WAV* files) and post that.

HI Graeme,
I'm running into problem with NEB, and could not able to proceed on the calculation, as discussed, please find my NEB files as attached. Kindly request your support on this calcualtion

I'm having a hard time making sense to this. This was run on dec. 6 with the error message:

/var/spool/pbs/mom_priv/jobs/120122.hn1-srmhpc03.SC: line 10: /opt/software/intel/parallel_studio_xe_2017.0.035/psxevars.sh: No such file or directory

This has nothing to do with the VTST code.