OH---CH4 optimization

Hello colleagues,

Am using PSI4 to optimize the OH—CH4 complex but am getting convergence errors. Any tips how how I can guide PSI4 achieve it. I have unsuccessfully tried several keyword combinations as shown below

molecule {
0 2
C 0.0424790000 0.0125640000 0.2218250000
H -0.0047750000 0.6029920000 1.1368470000
H 0.7040180000 0.5025090000 -0.4926030000
H -0.9559300000 -0.0725520000 -0.2071740000
O -1.1763740000 3.2013780000 -0.5200910000
H -1.4564860000 1.9510050000 0.3067870000
H 0.4261930000 -0.9817820000 0.4500580000
}
set {
#opt_coordinates both
#dynamic_level 0
basis cc-pVDZ
reference uhf
#full_hess_every 1
#geom_maxiter 200

step_type nr

intrafrag_step_limit 0.1

intrafrag_step_limit_min 0.1

intrafrag_step_limit_max 0.1

}

optimize(‘b3lyp’)

Thanks

What’s grep '~' your_output_file.out? As an untested guess, I’d drop the intrafrag*, step_type, and full_hess_every and just try dynamic_level 1.

Hi Loriab,

I finally got it to work by trying a different guess. Thanks for your suggestions.

Fred.