Transition probability of lithium atom and lithiumlike ions with weakest bound electron wave functions and coupled equations

One of us has presented a new theory called the Weakest Bound Electron Potential Model theory (WBEPM theory) to determine the exact potential field in atoms. A concise analytic form of the potential of the weakest-bound electron is proposed. In the new potential and the wave function derived afterward, the integral atomic number Z and quantum numbers n and l are replaced by nonintegral Z*, n*, and l*, respectively. In this article, we employed the WBEPM theory to calculate the transition probability for the lithium atom and lithiumlike ions and obtained very good results compared with the accepted values and other results.