CORE-EXCITED QUINTET STATES IN MG-I

The low-lying core-excited quintet states of Mg I have been studied experimentally and theoretically. On the basis of beam-foil spectroscopy, the energies of nearly all the quintet levels belonging to the 2p(5)3s3p2 and 2p(5)3s3p4s configurations have been established, while only 5F levels from the 2p(5)3s3p3d configuration could be identified. Multiconfigurational Hartree-Fock calculations, including the 2p(5)3s3p2, 3s3p3d, 3p3 and 3s3p4s configurations, have been performed to support the experimental assignments and to test the potentiality of this type of calculations to treat systems with a 2p5 core and three valence electrons. Good agreement is obtained between theory and experiment for the quintet levels belonging to the 2p(5)3s3p2 and 2p(5)3s3p4s configurations.