QE.ClCH3+Cl

Description:

An example of identifying a saddle point for a molecular reaction, an SN2 substitution:

Cl + CH₃Cl -> ClCH₃+ Cl

The ARTn input file artn.in specifies the initial push on three atoms, with indeces 1,2,6, corresponding to Cl,C, and Cl, respectively, which is constrained along the z axis. For this example the number and step size of the initial displacements is also increased:

push_mode = 'list'
push_ids = 1,2,6
add_const(3,1) = -0.2
add_const(3,2) = 0.2
add_const(3,6) = 1.0
ninit = 4
push_step_size = 0.6

Launch command: You can launch the example with the command: ./run_example.sh

Or as any QE calculation, by specifying the -partn flag:

mpirun -np N /QE_path/bin/pw.x -partn -in relax.ClCH3+Cl.in > relax.ClCH3+Cl.out

Expected results:

You should hopefully obtain similar results as the ones reported in directory reference.d, i.e., a barrier of 0.054 Ry (0.735 eV).