P,T-ODD SPIN-ROTATIONAL HAMILTONIAN FOR YBF MOLECULE

An ab initio relativistic effective core potential calculation of elec tronic wave function for the ground state ((2) Sigma) of a YbF molecul e is carried out followed by the restoration of molecular four-compone nt spinor behavior in the core region of ytterbium in the framework of a nonvariational procedure. The constructed spinors are used to evalu ate the spin-rotational Hamiltonian parameters including P- and P, T-o dd terms of the molecule.