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LHF
To run a LHF calculations select:
$dft
functional lhf
gridsize 3
This can be done using define (modified grid are not supported) and then run odft.
A more suitable procedure is the following:
 1)
 Do a HartreeFock calculation using dscf.
 2)
 Use the script lhfprep to prepare the
control file
(the old control file will be saved in control.hf and the
molecular orbitals in mos.hf or in alpha.hf and beta.hf
for the spinunrestricted case). See lhfprep help for options.
Actually LHF can be started from any guessed orbitals, but if HF orbitals
are used, a much faster convergence is expected.
By default the script lhfprep will add/modify the control file with:
$dft
functional lhf
gridtype 6
gridsize 3
radsize 3
$lhf
offdiag on
numslater off
asymptotic dynamic=1.d3
conjgrad conv=1.d6 maxit=20 output=1 asy=1
slaterdtresh 1.d9
slaterregion 7.0 0.5 10.0 0.5
corrctregion 10.0 0.5
$scfdump
$scfiterlimit 30
$scfconv 6
$scfdamp start=0.000 step=0.500 min=0.50
$scforbitalshift noautomatic
$correction matrixelements file=lhfcg
$correction alpha matrixelements file=lhfcg_alpha
$correction beta matrixelements file=lhfcg_beta
 3)
 Run odft.
With the LHF potential Rydberg series of virtual orbitals
can be obtained. To that end, diffuse orbital basis sets have to
be used and special grids are required.
gridtype 4
is the most diffuse with special radial scaling;
gridtype 5
is for very good Rydberg orbitals;
gridtype 6
(default in Lhfprep) is the least diffuse,
only for the first Rydberg orbitals.
Only gridsize 35 can be used, no modified grids.
Use testinteg
to check if the selected grid is accurate enough for the
employed basisset, see page .
The options in the $lhf group are:


 offdiag on

The LHF exchange potential is computed (default);
 offdiag off

The KLI exchange potential is computed (can be selected by lhfprep kli).
 numslater on

the Slater potential is calculated numerically everywhere: this is
more accurate but quite expensive. When ECPs are used, turn on this option.
It can be selected by lhfprep num.
 numslater off

the Slater potential is computed using basissets. This leads to very fast calculations, but
accurate results are obtained only for firstrow elements or if an uncontracted basis set or a basis set
with special additional contractions is used. This is the default.
 asymptotic

for asymptotic treatment there are three options:
 asymptotic off

No asymptotictreatment and no use
of the numerical Slater. The total exchange potential is
just replaced by 1/r
in the asymptotic region.
This method is the fastest one but can be used only for the
densitymatrix convergence or if Rydberg virtual orbitals are of no interest.
 asymptotic on

Full asymptotictreatment and use
of the numerical Slater in the near asymptoticregion. It can be selected by lhfprep asy.
 asymptotic dynamic=1.d3

Automatic switching on (off) to the special asymptotic treatment if the
differential densitymatrix rms is below (above) 1.d3.
This is the default.
 potfile save

the converged
Slater and correction potentials for all grid points
are saved in the files slater.pot
and corrct.pot
, respectively.
Using potfile load
, the Slater potential
is not calculated but read from slater.pot
(the
correction potential is instead recalculated).
For spin unrestricted calculations the corresponding files are
slaterA.pot
, slaterB.pot
, corrctA.pot
and
correctB.pot
.
 homo

allows the user to specify which occupied orbital
will not be included in the calculation of correction potential: by default
the highest occupied orbital is selected. This option is useful for those
systems where the HOMO of the starting orbitals (e.g. EHT, HF) is different
from the final LHF HOMO. homob
is for the beta spin.
 correlation func=functional

a correlation functional can be added to the LHF potential:
use func=lyp
for LYP, or func=vwn
for VWN5 correlation.
For other options see 18.2.6.
Next: How to plot the
Up: How to Perform
Previous: OEPEXX
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TURBOMOLE M