Inner-shell photodetachment of Li-

Absolute cross section for photodetachment of Li- ions near the 1s threshol d leading to Li+ formation has been measured by overlapping a beam of Li- i ons with synchrotron radiation from an undulator. Multiple excitation to th e core-excited Li 1s(2s2p P-3) P-2 and Li 1s(2p3s (3)p) (2)p states, i.e. c onjugate shakeup, is found to be much stronger than observed for any neutra l atom or positive ion, reflecting the dominant influence of electron corre lation for negative ions. The cross section for multiple excitation is sign ificantly larger than for single excitation.