MAGNETIC CIRCULAR-DICHROISM OF 3D-2P AND 4D-2P X-RAY-EMISSION IN RARE-EARTHS

We discuss features of magnetic circular dichroism (MCD) of X-ray emis sion spectrum in the 3d-->2p and 4d-->2p radiative transition (3d-2p X ES and 4d-2p XES: respectively) combined with the 2p core excitation w ith the circularly polarized light in rare earths on the basis of an a tomic calculation including the full multiplet. The calculated 4d-2p(3 /2) and 3d-2p(3/2) XES and MCD for Gd3+ are in good agreement with the recent experimental result for Gd metal. An approximate separation of 4d(5/2) and 4d(3/2) components as well as of 3d(5/2) and 3d(3/2) is s hown to be possible in the present spectroscopy: which is impossible i n an ordinary 4d core spectroscopies. A dispersive MCD spectrum of XES in both the 2p(3/2) and 2p(1/2) core excitations, a difference in the emitted photon energy dependence of the sign of MCD spectra between t he two excitations and an opposite tendency of MCD spectra between the less-than-half and more-than-half filled 4f shells are discussed in t erms of the 4f-3d (or 4d) exchange interactions for the magnetized Hun d rule ground state.