Two-neutrino double- β decay of 94 ⩽ A ⩽ 110 nuclei for the 0

The two-neutrino double-beta decay of 94, 96Zr,98,100Mo,104Ru and 110Pd nuclei for the 0+↦0+ transition is studied in the PHFB model in conjunction with the summation method. In the first step, the reliability of the intrinsic wave functions has been established by obtaining an overall agreement between a number of theoretically calculated spectroscopic properties and the available experimental data for 94, 96Zr,94,96,98,100Mo, 98,100,104Ru, 104,110Pd and 110Cd isotopes. Subsequently, the PHFB wave functions of the above-mentioned nuclei are employed to calculate the nuclear transition matrix elements M 2ν as well as half-lives T 1/2 2ν. Furthermore, we have studied the effects of deformation on the M 2ν