The method of supersonic free-jet expansion beam combined with techniques of laser spectroscopy was used in an investigation of vibronic and isotopic structures in the D(1)0(u)(+)(6(1)S(0)) and F(3)1(u)(6(3)P(2)) electronic energy Rydberg states of Cd-2. Laser-induced fluorescence excitation spectra recorded using the D(1)0(u)(+) <- X(1)0(g)(+)(5(1)S(0)) and F(3)1(u) <- X(1)0(g)(+) transitions in the region of 206-218 nm provided spectroscopic characteristics of the excited states and allowed constructing of their intratomic potentials. Isotopic structures recorded in the (v',v '') bands of the D(1)0(u)(+) <- X(1)0(g)(+) transition were used in determination of the D(1)0(u)(+) state vibrational characteristics (omega(e)'x(e)', omega(e)'x(e)') and v' assignment The nu(0,0) recorded directly in the F(3)1(u) <- X(1)0(g)(+) transition enabled determination of the bottom of the F(3)1(u) state potential well. Valence ab initio calculations of Cd-2 interatomic potentials were performed with relativistic and spin orbit effects taken into account. The experimental results were compared with results of the ab initio calculations. A free-jet expansion of Cd-2 as a source of entangled atoms for a test of Bell's inequality was analyzed.