  Wavefunction at the origin with the incorporation of relativistic effect
leads to singularity in a specific potential model. To regularise the
wavefunction, we introduce a short distance scale here and use it to estimate
masses and decay constants of Bd and Bs mesons within the QCD potential
model.These values are then used to compute the oscillation frequency \Delta mB
of Bd and Bs mesons. The values are found to be in good agreement with
experiment and other theoretical values.
