infsao provides
information about the symmetry adapted basis which is used for the
SCF-calculation. To exploit the molecular symmetry as efficiently as
possible, TURBOMOLE programs do not use the simple basis which you
specified during your define session. Instead it builds linear
combinations of equal basis functions on different--but symmetry
equivalent--atoms. This basis is then called the SAO-basis
(Symmetry Adapted Orbital). It has the
useful property that each basis function transformed to this basis
transforms belongs to one irreducible representation of the
molecular point group (that is, the basis reflects the full
molecular symmetry as specified by the Schönflies symbol).
infsao gives you a listing of all symmetry adapted basis
functions and their constituents either on file or on the screen.
This may help you if you want to have a closer look at the SCF
vectors, because the vector which is output by program dscf is
written in terms of these SAOs.
atbandbta can
be used to transform existing mos, alpha, and beta files
from ASCII to binary format and vice versa.
eht performs an extended Hückel calculation for your
molecule. The orbital energies available from this calculation are
then used to provide occupation numbers for your calculation and the
Hückel MOs will be projected onto the space that is spanned by
your basis set. This start-vectors are not as good as the ones which
may be obtained by projection of an old SCF vector, but they are
still better than the core Hamiltonian guess that is used if no
start vectors are available. When using this command, you will be
asked if you want to accept the standard Hückel parameters and to
enter the molecular charge. Afterwards you will normally get a list
of the few highest occupied and lowest unoccupied MOs, their
energies and their default occupation. If you don't want to accept
the default occupation you will enter the occupation number
assignment menu, which is described in Section 4.3.2. Note
that the occupation based on the Hückel calculation may be
unreliable if the difference of the energies of the HOMO and the
LUMO is less than 0.05a.u. (you will get a warning). You will
also have to enter this menu for all open-shell cases other than
doublets.
use you are able
to use information about occupied MOs and start vectors from a
former calculation on the same molecule. file should be the
path and name of the control file of this former
calculation, of which all data groups related to occupation numbers
and vectors will be read. As the new generated data will overwrite
the existing data if both resist in the same directory, it is best
and in some cases necessary to have the data of the former
calculation in another directory than the one you started the
define session in. Then just type use <path>/control to
construct a new SCF vector from the data of the old calculation,
without changing the old data. The data groups $closed shells
and $open shells will be taken for your new calculation and
the SCF vector from the old calculation will be projected onto the
space which is spanned by your present basis set. These start
vectors are usually better than the ones you could obtain by an
extended Hückel calculation.
--------------------------------------------------------- actual closed shell orbital selection range --------------------------------------------------------- a1 # 1- 18 a2 # 1- 1 e # 1- 13 --------------------------------------------------------- any further closed-shell orbitals to declare ? DEFAULT(y)If you answer this question with y, you enter the orbital specification menu which will be described in Section 4.3.3.
The same procedure applies to the open-shell occupation numbers after you finished the closed-shell occupations.
hcore tells programs dscf
and ridft to run without a start vector (it writes the data
group $scfmo none to file control). dscf or
ridft will then start from the core Hamiltonian start vector,
which is the vector obtained by diagonalizing the one-electron
Hamiltonian. Note that you still have to specify the occupation
numbers. This concerns only the first SCF run, however, as for the
following calculations the converged vector of the previous
iteration will be taken. A SCF calculation with a core Hamiltonian
start vector typically will take 2 - 3 iterations more than a
calculation with an extended Hückel start vector (a calculation
with the converged SCF vector of a previous calculation will need
even less iterations, depending on how large the difference in the
geometry between the two calculations is).