TABLE OF CONTENTS

36c-sbco-N2OPd

DESCRIPTION

How to make a SBCO calculation for dissociation of N2O on Pd(110).

SBCO stands for Scan-Bond Constrained-Optimization, i.e., a series of pw.x constrained optimizations with a specified bond being step-wise elongated, optionally followed by a neb.x calculation to verify the transition state and activation energy.

BEWARE

This method is applicable only for reactions with reaction coordinate predominantly along a bond direction. A serious caveat of this method is that it may completely miss the transition state, yielding a considerably underestimated activation energy. For this reason, a post-NEB calculations can be performed.

EXAMPLE SOURCE FILE

sbco-N2OPd.pwtk

SOURCE

# input data for N2O/Pd(110) is imported from N2OPd.pwtk with ::pwtk::import
import N2OPd.pwtk


# specs for SBCO calculation with full pw.x relaxation of the last
# image (post_relax = true) and post neb.x (post_neb = true)
# calculation to get more accurate activation energy

SBCO {
    bond       =  1 2
    mass       =  1.0 4.0
    nsteps     =  6
    increment  =  0.15
    unit       =  angstrom
    tolerance  =  0.0001
    auto       =  false
    first_opt  =  true
    post_relax =  true
    post_neb   =  true    
}

# let's use num_of_images = 3 for the post_neb calculation

PATH { num_of_images = 3 }

# the FLO workflow is run with 'sbco_run' (or ::pwtk::sbco::run)

sbco_run sbco.N2O-Pd110-c2x2-3L