Many-body Calculation Of Fine-Structure Intervals Of Np States Of Na

We used the method of Numerov algorithm to solve the relativistic Hartree-Fock equation of atomic system, and we can get the numerical solution of the virtual eigenfunction and the occupied eigenfunction. Using the modified Numerov algorithm can choose the various step sizes, so the mothed is more flexible when we solve the relativistic Hartree-Fock equation of Na, and that make it possible to ensure the accuracy of the result when we cut the amount of calculation. It should emphasize that a zeroth-order potential was modified by the presence of an exponential when we solve the relativistic Hartree-Fock equation of virtual states, and that will eliminate the number of the continuum states and make the calculation more convenience. On that basis we take the Breit and the correlation energy between the electrons into account, we calculate the second-order MBPT and the first-order perturbation of the Breit, then we can obtain the numerical value of the fine-structure intervals of Na. Compare with the experimental date, it is shown that the numerical value of the fine-structure intervals we calculate is very close to the experimental date,that is grate.