  The scalar-pseudoscalar interaction constant of PbF in its ground state
electronic configuration is calculated using the Z-vector method in the
relativistic coupled-cluster framework. The precise calculated value is very
important to set upper bound limit on P,T-odd scalar-pseudoscalar interaction
constant, k_s, from the experimentally observed P,T-odd frequency shift.
Further, the ratio of the effective electric field to the scalar-pseudoscalar
interaction constant is also calculated which is required to get an independent
upper bound limit of electric dipole moment of electron, d_e, and k_s and how
these (d_e and k_s) are interrelated is also presented here.
