# [molpro-user] turning off dkroll

Benj FitzPatrick benjfitz at uchicago.edu
Thu Jun 12 23:45:13 BST 2008

```Hello,
I was interested in seeing the effect of DKHO on the relativistic calculation
and wanted to put this into a loop.  What do I need to do in order to compare
these results with ones where I only compute one DKH energy in the job and run a
lot of jobs?  Namely, I want to turn dkroll off (and dkroll=0 doesn't appear to
do it) b/c I have some preliminary HF calcs (some of the radicals I'll be
studying don't converge unless I start with a small basis set) with smaller
basis sets and I don't want them doing DKH calculations.  I gave a portion of
the input file below.
Thanks,
Benj FitzPatrick
University of Chicago

basis=6-31G*;
{hf;
wf,40,1,0}
basis=6-311G**;
{hf;
wf,40,1,0}
basis,default=aug-cc-pvdz,cl=avdz+d;
{hf;
wf,40,1,0}
eref1=energy

dkhp=1
i=0
do dkhorder=2,6,1
i=i+1
!I need to turn off dkroll here

basis=6-31G*;
{hf;
wf,40,1,0;
start,atdens}

basis=6-311G**;
{hf;
wf,40,1,0}
dkroll=1

basis,default=aug-cc-pvdz,cl=avdz+d;
{hf;
wf,40,1,0}
dkho=dkhorder
{hf;
wf,40,1,0}
enddo

```