  The conventional parametrizations of lattice static interquark force are
shown to produce a mismatch of coupling constant near the matching point R_m
\approx 0.2 fm. The running coupling constant of the background perturbation
theory yields instead a selfconsistent description of lattice data over all
interval of distances, 0.05 fm \la R \la 1.1.fm, and is an analytic function
with the property of asymptotic freedom at small R and it is freezing at large
R.

High Energy Physics - Lattice