Threshold Photoelectron Spectroscopy of HF in the Inner Valence Ionization Region A.J. Yencha(1), M.C.A. Lopes(2,3), M.A. MacDonald(4), G.C. King(2) (1) University at Albany (2) Manchester University (3) Universidade Federal de Juiz de Fora (4) CLRC Daresbury Laboratory The threshold photoelectron (TPE) spectrum of hydrogen fluoride has been re- corded at good resolution (about 50 meV) encompassing the inner valence ion- ization region. The TPE spectrum is characterized by the dominant "main-line" for (2ssigma)-1 ionization followed by an extensive region of broad satellite ion bands. The results of this study contrast with the findings for TPES of the inner valence ionization region of the heavier halogen acids.