Absence of U 5f band states in resonant photoemission spectra of UPd2Al3

The U 5f spectral weight of UxLa1-xPd2Al3 (x=0.1, 0.25, 0.6, and 1.0) is ob tained by the resonant photoemission spectroscopy (RPES), and is compared w ith the results of the band-structure calculations. We have found that the spectrum of UPd2Al3 (x=1) could not be reproduced by the calculated U 5f de nsity of states in shape and position, even if the contribution from U Sd s tates is considered. Moreover, the essential spectral shape did not change until x=0.1, where most of the uranium atoms are substituted with lanthanum atoms. All these results indicate that the U 5f band states are not observ ed in the RPES spectrum of UPd2Al3, and the single site effects govern it. [S0163-1829(99)01215-1].