The standard thermodynamic functions (Cp°,S°,H° and (G°−H0°)/T) at 100 to 1000 K of 24 polyatomic gaseous ions are reported, based on structural and spectroscopic data from the literature. These ions supplement the 130 ions previously studied and are: zirconyl, hydrotelluride, amide, selenocyanate, tellurocyanate, orthoborate, metaphosphate, arsenite, orthosilicate, tetrachloropalladate(II), tetrabromopalladate(II), tetrachloroplatinate(II), tetrabromoplatinate(II), hexafluorophosphate, hexafluoroarsenate, hexafluoroantimonate, hexabromoplatinate(IV), tetracyanonickelate, tetracyanomercurate, octacyanomolybdate(IV), sulfamate, benzoate, guanidinium, and glycine as cation, zwitterion, and anion. ©1996 American Institute of Physics and American Chemical Society.