MOLPRO

39 THE VB PROGRAM CASVB 289
given for the total CASSCF wavefunction, as well as the orthogonal complement to Ψ V B . The
default for the number of configurations requested, N conf , is 10. If N conf =−1 all configurations
are included.
39.12 Controlling the amount of output
PRINT,i 1 , i 2 ,. . . ;
Each number specifies the level of output required at various stages of the execution, according
to the following convention:
-1 No output except serious, or fatal, error messages.
0 Minimal output.
1 Standard level of output.
2 Extra output.
The areas for which output can be controlled are:
i 1
i 2
i 3
i 4
i 5
i 6
Print of input parameters, wavefunction definitions, etc.
Print of information associated with symmetry constraints.
General convergence progress.
Progress of the 2nd order optimization procedure.
Print of converged solution and analysis.
Progress of variational optimization.
i 7 Usage of record numbers on file 2.
For all, the default output level is +1. If i 5 ≥2 VB orbitals will be printed in the AO basis
(provided that the definition of MOs is available); such output may be especially useful for
plotting of orbitals.
39.13 Further facilities
Calculations can also be performed for various types of direct product wavefunctions and/or
with strictly localized orbitals. Details are available from the authors. These facilities will be
documented in a later release.
39.14 Service mode
SERVICE;
This keyword takes precedence over any others previously defined to CASVB. It provides simple
facilities for retrieving orbital coefficients and VB structure coefficients. It should not be used
during a run of CASVB that has been invoked from inside MULTI.
START,record.file;
Coefficients are taken from record.file. The default value is 2100.2.
WRITE,iwrite;
Vectors in the symmetry orbital basis are written to channel iabs(iwrite). The default action is