Electron-correlation effects in the g factor of light Li-like ions

We investigate electron-correlation effects in the g factor of the ground state of Li-like ions. Our calculations are performed within the nonrelativistic quantum electrodynamics (NRQED) expansion up to two leading orders in the fine-structure constant alpha, alpha(2), and alpha(3). The dependence of the NRQED results on the nuclear charge number Z is studied and the individual 1/Z-expansion contributions are identified. Combining the obtained data with the results of the all-order (in Z alpha) calculations performed within the 1/Z expansion, we derive unified theoretical predictions for the g factor of light Li-like ions.