Role of hyperfine interaction in Landé g-factors of 3P0o clock states

•In the weak-magnetic-field approximation, we calculated the hyperfine-induced Landé g-factors of the 3P0o clock states in 27Al+ and 87Sr by using the multi-configuration Dirac–Hartree–Fock method. The present results, δghfs(1)(3P0o)=−1.183(6)×10−3 for 27Al+ and δghfs(1)(3P0o)=7.78(30)×10−5 for 87Sr, agree with experimental values very well.•We also estimated the contributions from perturbing states to the g-factors concerned so as to truncate the summation over the perturbing states without loss of accuracy.•The computational uncertainties were systematically analyzed. In the weak-magnetic-field approximation, we calculated the hyperfine-induced Landé g-factors of the 3P0o clock states in 27Al+ and 87Sr by using the multi-configuration Dirac–Hartree–Fock method. The present results, δghfs(1)(3P0o)=−1.183(6)×10−3 for 27Al+ and δghfs(1)(3P0o)=7.78(30)×10−5 for 87Sr, agree with experimental values very well. The influence of relativistic effects and electron correlations on the involving hyperfine interaction and Zeeman matrix elements, and energy separations were investigated in detail. We also estimated the contributions from perturbing states to the g-factors concerned so as to truncate the summation over the perturbing states without loss of accuracy. Based on these, the computational uncertainties were systematically analyzed for the hyperfine-induced Landé g-factors of the 3P0o clock states in these two atomic systems.