Time-of-flight mass spectrometry has been used to examine positive and negative ions desorbed by keV cesium ion bombardment, in high vacuum, of gold surfaces prepared by vapor deposition of gold onto a silver or glass substrate at an ambient pressure of similar to 1 Pa. Many negative ions containing gold, oxygen, and hydrogen were detected; the only positive ion observed, but in small amounts, was Au+. The most abundant of the negative ions were Au-, AuO2Hn- (n = 1-6), AuO3Hn-, (n = 2-4, 6), Au2O4Hn-, (n = 2-8, 10), AU(2)O(5)H(n)(-) (n = 3-9, 11), AU(3)O(6)H(n)(-) (n = 3-8, 10), AU(3)O(7)H(n)(-) (n = 6-9, 11), and several more oligomeric ions with a higher gold content. The relative peak height variations for ions belonging to the AuxO2xHy-, and AuxO2x+1Hz- series (x = 2 or 3) exhibited strikingly similar patterns for a given value of x, with an mit difference of 17 between corresponding parts of the two patterns. Even- and odd-electron compositions are of approximately equal prominence. To account for the abrupt ends of the sequences, the negative ion compositions are rationalized by structures in which the valence shell electron count for gold is less than or equal to 18. Some proposals for the 18-electron structures are made. These structures are similar to, but also show differences from, known structures of neutral gold fluorides.