16.1 Input options

The calculation of core-polarization matrix elements is invoked by the CPP card, which can be called at an arbitrary position in the MOLPRO input, provided the integrals have been calculated before. The CPP card can have the following three formats:

• CPP,INIT,ncentres;
• CPP,ADD[,factor];
• CPP,SET[,fcpp];

CPP,INIT,$<ncenters>$;

abs($<ncenters>$) further cards will be read in the following format:

$<atomtype>,<ntype>,<\alpha_d>,<\alpha_q>,<\beta_d>,<cutoff>$;

$<atomtype>$ corresponds to the recognition of the atomic centres in the integral part of the program,
$<ntype>$ fixes the form of the cutoff-function (choose 1 for Stoll/Fuentealba and 2 for Mueller/Meyer);
$<\alpha_d>$ is the static dipole polarizability,
$<\alpha_q>$ is the static quadrupole polarizability,
$<\beta_d>$ is the first non-adiabatic correction to the dipole-polarizability and
$<cutoff>$ is the exponential parameter of the cutoff-function.

When $<ncenters>$ is lower than zero, only the integrals are calculated and saved in the record 1490.1. Otherwise, the $h_0$ matrix (records 1200.1 and 1210.1) and the two-electron-integrals (record 1300.1) will be modified.

CPP,ADD,$<factor>$;

With this variant, previously calculated matrix elements of the polarization matrix can be added with the variable factor $<factor>$ (default: $<factor>$ = 1) to the $h_0$-matrix as well as to the two-electron-integrals. In particular, CPP,ADD,-1.; can be used to retrieve the integrals without the polarization contribution.

CPP,SET,$<fcpp>$;

normally not necessary but may be used to tell MOLPRO after a restart, with what factor the polarization integrals are effective at the moment.