Currently not implemented in the UKRmol+ suite.

ZEFF aims to calculate the annihilation parameter Z_{eff} for positron 
calculations. This program produces the necessary delta matrix Z_{ij} which
is saved to file fort.122. 

Before running ZEFF, job of GAUSDELTA need to run for getting delta integrals
(see test jobs inner.job). flags LUMPS (in congen) and LUSME (in scatci) should
be switched on for getting symbolic matrix element which is saved to file 
LUSME. So, fort.13, fort.16 (delta integrals not mo integrals), fort.25, 
fort.[LUMPS] and fort.[LUSME] are needed for running ZEFF. 
