  Electron impact excitation collision strengths are calculated for all
transitions among 113 levels of the 2s$^2$2p$^5$, 2s2p$^6$,
2s$^2$2p$^4$3$\ell$, 2s2p$^5$3$\ell$, and 2p$^6$3$\ell$ configurations of
F-like W~LXVI. For this purpose Dirac Atomic R-matrix Code (DARC) has been
adopted and results are listed over a wide energy range of 1000 to 6000 Ryd.
For comparison purpose analogous calculations have also been performed with the
Flexible Atomic Code (FAC), and the results obtained are comparable with those
from DARC.
