This card is used to specify a reference configuration set other than a CAS,
which is the default. Configurations can be defined using CON cards, which
must appear after the SELECT card. Alternatively, if ref1 is
an existing MOLPRO record name, the configurations are read in from that
record and may be selected according to a given threshold.
The select card must be placed directly after the WF or REF card(s),
or, if present, the RESTRICT cards. The general order of these cards is
WF (or REF)
- (rec12000) The configurations are read in
the specified record. See section 19.5.5 about how to save the configurations
in the MCSCF calculation. If ref1 is not specified, the
program assumes that the configurations are read from
subsequent CON cards (see CON).
- (rec22000) additional configurations are
the specified record. If rec2 is negative, all
records between rec1 and abs(rec2) are read.
All configurations found in this way are merged.
- Selection threshold for configurations read from
(records rec1-rec2). This applies to the norm
of all CSFs for each orbital configuration.
- Specifies from which state vector the
are selected. This only applies to the case that the
configurations were saved in a state-averaged calculation.
If refstat is zero or not specified, the configurations are selected
from all states.
If refstat is greater than zero, then the specified reference state is used.
If refstat is less than zero, then all appropriate reference states are used.
Lastly, if refstat is of the form istat1.istat2, states istat1 through istat2
- maximum number of open shells in the selected or