Hi, all friends,
I have got PES Scan converge issue in HF molecule, the input is like below:
memory 8 GB
molecule HF_mol{
0 1
H
F 1 R
#Symmetry c1
}
#Rvals=[0.5,0.6,0.7,0.8,0.9,1,1.1,1.2,1.3,1.4,1.5,1.6,1.7,1.8,1.9,2,2.1,2.2,2.3,2.4,2.5,2.6,2.7,2.8,2.9,3,3.1,3.2,3.3,3.4,3.5,3.6,3.7,3.8,3.9,4,4.1,4.2,4.3,4.4,4.5,4.6,4.7,4.8,4.9,5,5.1,5.2,5.3,5.4,5.5,5.6,5.7,5.8,5.9,6]
Rvals=[2.3,2.4,2.5,2.6,2.7,2.8,2.9,3,3.1,3.2,3.3,3.4,3.5,3.6,3.7,3.8,3.9,4,4.1,4.2,4.3,4.4,4.5,4.6,4.7,4.8,4.9,5,5.1,5.2,5.3,5.4,5.5,5.6,5.7,5.8,5.9,6]
DFT_functionals=[]
set {
basis aug-pcseg-3
guess SADNO
#DAMPING_PERCENTAGE 20
#LEVEL_SHIFT 0.25
soscf false
#MOM_START 0
reference rhf
#FRAC_DIIS true
scf_type PK
e_convergence 10
dft_spherical_points 590 # Often needed
dft_radial_points 135 # Often needed
dft_radial_scheme treutler # Rarely needed
dft_pruning_scheme robust # Generally safe and will speed things up
}
E_Dipole = {}
E_energy = {}
for R in Rvals:
HF_mol.R = R
E_energy[R] = energy('PBE')
E_Dipole[R] = properties('PBE', properties=['dipole'])
for R in Rvals:
e = E_energy[R]
d = E_Dipole[R]
psi4.print_out("%3.1f %10.6f %10.6f\n" % (R, e, d))
previous points (when R < 2.2), the SCF are converged very well, after that, converges are very difficult. the sysytem Occupation by irrep changed frequently,PSI4 can not get a converge results.
I have tried many many combinations: change the initial guess, Damp,levelshift,MOM, trunoff Symmetry …
SOSCF could help in some case, but also failed at R=2.5, and there is drawback that SOSCF can not use in meta-gga?
By the way, use the very same input in ORCA, I have got very smooth PES without any issue.
So, any possibility do these PES job further?