r2scan very slow (not scf but doing extra calculations)

How To
#1

HI, I am noticingmany thins are written during a simple scf calculations of r2scan. I don’t want to write those things. For example I don’t want to do extrac calculations such as

#-----------------------------------------------

Performing Pipek-Mezey Localization.
Localization complete after 4 iterations.
Performing Pipek-Mezey Localization.
Localization complete after 5 iterations.
Performing Pipek-Mezey Localization.
Localization complete after 50 iterations.

 Iter      Energy         Gradient      Stepsize

GVB: 1 -1620.7566721099 0.24618984 0.09158684 Descent step
GVB: 2 -1620.7891983320 0.30721778 0.05663467 Descent step
GVB: 3 -1620.7592477655 0.71921332 0.02355084 Line search: overstep
GVB: 4 -1620.8002228864 0.17942867 0.01508948 Descent step
GVB: 5 -1620.8039179007 0.18845671 0.04493470 Normal BFGS step
GVB: 6 -1620.8105680629 0.08561017 0.04150361 Normal BFGS step
GVB: 7 -1620.8068748823 0.14700968 0.01871209 Line search: overstep
GVB: 8 -1620.8138137476 0.04445328 0.01889968 Descent step
GVB: 9 -1620.8111239829 0.08820470 0.00824997 Line search: overstep
GVB: 10 -1620.8155254946 0.03180382 0.01746618 Normal BFGS step
GVB: 11 -1620.8172100161 0.03168761 0.01383661 Normal BFGS step
#---------------------------------------------------

for the input file

$comment
AlCl3
$end

$molecule
0 1
Al .000000 .000000 .000000
Cl .000000 2.069041 .000000
Cl 1.791842 -1.034520 .000000
Cl -1.791842 -1.034520 .000000
$end

$rem
jobtype = sp
SCF_CONVERGENCE = 5
exchange = r2scan
correlation = r2scan
basis = def2-QZVP
xc_grid = 000099000590
scf_algorithm = diis
thresh = 14
scf_final_print = 1
symmetry = false
sym_ignore = true
mem_static = 8192
mem_total = 16384
$end

I am using version 6.2

How can I write only SCF energy without extra calculations like

An efficient Perfect Pairing Calculation will be performed…
Orbital Subspaces
Alpha: 20 Core, 12 Act Occ, 12 Act Vir,
236 Inact Vir
Beta : 20 Core, 12 Act Occ, 12 Act Vir,
236 Inact Vir
***************************
Performing Pipek-Mezey Localization.
Localization complete after 4 iterations.
Performing Pipek-Mezey Localization.
Localization complete after 5 iterations.
Performing Pipek-Mezey Localization.
Localization complete after 50 iterations.

 Iter      Energy         Gradient      Stepsize

GVB: 1 -1620.7566721099 0.24618984 0.09158684 Descent step
GVB: 2 -1620.7891983320 0.30721778 0.05663467 Descent step
GVB: 3 -1620.7592477655 0.71921332 0.02355084 Line search: overstep
GVB: 4 -1620.8002228864 0.17942867 0.01508948 Descent step

I don’t want to calculate this.

#2

Hi Subrata,
I can reproduce this in Q-Chem 7.0. It’s a strange bug but it has a simple workaround. Instead of setting EXCHANGE and CORRELATION separately, please set METHOD=R2SCAN instead. That has been the convention going back a long time, we preserved EXCHANGE and CORRELATION for backwards compatibility but in this isolated case that’s somehow triggering extra post-SCF stuff that you don’t want, which is what’s taking the time.

This fix works with Q-Chem 7.0, please reply if it doesn’t work with your version.