SYSTEMATIC TRENDS IN THE LINE STRENGTHS OF E1 TRANSITIONS IN THE CARBON ISOELECTRONIC SEQUENCE

Line strengths S for the dipole allowed transitions within the n = 2 c omplex of the carbon isoelectronic sequence have been fitted in the fo rm Z(2)S = A + B/(Z - C), where Z is the nuclear charge of a particula r ion. The constants A, B and C are determined by using a non-linear l east square method. The data for S is taken from the configuration int eraction calculations which included internal, semi-internal and all e xternal type correlations for ions in the range Z = 8 - 26. It is show n that the values of A obtained from the fit for all the transitions a re in excellent accord with the ab-initio values obtained in the hydro genic limit Z --> infinity provided near degeneracy effects are includ ed.