Reaction path for the charged adsorbates system
Posted: Sat Oct 01, 2022 7:37 am
Dear Professor:
I have been working on the dissociated path of a charged adsorbates on SWNT. I constructed a finite length carbon nanotube with charged peroxodisulfate ions (with +2e) adsorbed on it. The transition state calculations for the reaction path have been converged under vacuum, after which I have added implicit solvation parameters (EB_k = 80, LSOL = .TRUE.) to calculate the single point energy of each reaction state to get the solvation effect on this reaction. However, the energy of the transition state obtained from solvation calculation is lower than the initial state, which is obviously unreasonable (the reaction energy barrier is around 1 eV under vacuum).
1. Is it possible to qualitatively reflect the trend of the reaction path by only calculating the single point energy under implicit solvation? Is it necessary to include solvation parameters for transition state calculations? This requires too much computational resources to be consumed.
2. Is it available for vasp-vtst to calculate the reaction paths of charged adsorbates, and is it necessary to add other parameters besides NELECT?
3. Is the implicit solvation accurate for the energy calculation of the ions? Although this is not related to vtst's code, I will be glad to hear your opinion since I haven't got a reply in vaspsol's forum yet.
Here are my INCAR parameters for the single point calculation with solvation:
PREC = Accurate
ENCUT = 520.000
NPAR=4
ISYM=0
IDIPOL=4
LSOL = .TRUE.
EB_K = 80
IBRION = -1
NSW = 1
ISIF = 2
NELMIN = 2
EDIFF = 1.0e-05
EDIFFG = -0.03
VOSKOWN = 1
NBLOCK = 1
NWRITE = 1
NELECT = 690.0
ISYM = 0
NELM = 200
ALGO = Fast
IVDW = 12
VDW_S6 = 1.000
VDW_S8 = 0.7875
VDW_A1 = 0.4289
VDW_A2 = 4.4407
INIWAV = 1
ISTART = 1
ICHARG = 0
LWAVE = T
LCHARG = .FALSE.
ADDGRID = .FALSE.
ISMEAR = 0
SIGMA = 0.05
LREAL = Auto
LSCALAPACK = .FALSE.
RWIGS = 0.77 0.32 0.73 1.02 0.99
I have been working on the dissociated path of a charged adsorbates on SWNT. I constructed a finite length carbon nanotube with charged peroxodisulfate ions (with +2e) adsorbed on it. The transition state calculations for the reaction path have been converged under vacuum, after which I have added implicit solvation parameters (EB_k = 80, LSOL = .TRUE.) to calculate the single point energy of each reaction state to get the solvation effect on this reaction. However, the energy of the transition state obtained from solvation calculation is lower than the initial state, which is obviously unreasonable (the reaction energy barrier is around 1 eV under vacuum).
1. Is it possible to qualitatively reflect the trend of the reaction path by only calculating the single point energy under implicit solvation? Is it necessary to include solvation parameters for transition state calculations? This requires too much computational resources to be consumed.
2. Is it available for vasp-vtst to calculate the reaction paths of charged adsorbates, and is it necessary to add other parameters besides NELECT?
3. Is the implicit solvation accurate for the energy calculation of the ions? Although this is not related to vtst's code, I will be glad to hear your opinion since I haven't got a reply in vaspsol's forum yet.
Here are my INCAR parameters for the single point calculation with solvation:
PREC = Accurate
ENCUT = 520.000
NPAR=4
ISYM=0
IDIPOL=4
LSOL = .TRUE.
EB_K = 80
IBRION = -1
NSW = 1
ISIF = 2
NELMIN = 2
EDIFF = 1.0e-05
EDIFFG = -0.03
VOSKOWN = 1
NBLOCK = 1
NWRITE = 1
NELECT = 690.0
ISYM = 0
NELM = 200
ALGO = Fast
IVDW = 12
VDW_S6 = 1.000
VDW_S8 = 0.7875
VDW_A1 = 0.4289
VDW_A2 = 4.4407
INIWAV = 1
ISTART = 1
ICHARG = 0
LWAVE = T
LCHARG = .FALSE.
ADDGRID = .FALSE.
ISMEAR = 0
SIGMA = 0.05
LREAL = Auto
LSCALAPACK = .FALSE.
RWIGS = 0.77 0.32 0.73 1.02 0.99