Multiconfiguration Dirac-Hartree-Fock calculations of the forbidden transitions between 3s2 1S0, 3s3p 3P0,1,2, 1P1 states for Mg-like ions

Weak forbidden transitions are of great interest for plasma diagnostics, but they are sensitive to many factors in theoretical calculations. In earlier work on the intercombination transition using the multiconfiguration Dirac-Hartree-Fock approach for Al+-S4+ ions, a method was developed to eliminate the dependence of the transition rates on the optimization strategy. In this paper, this method is applied to other LS forbidden transitions. For the LS allowed transitions the transition energy normalization can eliminate such a dependence. It is also found that the fine structure splittings corrected by the non-relativistic limit offsets are independent of optimization strategies and are in good agreement with observations. For the high-Z ions, the dependence on strategies is less important and the calculations for all the transitions (E1, E2, M1, M2) are extended to Z = 92. A general scaling formula is adopted to reduce the extensive variation of the rates with respect to the nuclear charge.