Chromium(111) chelates of four monothio-ß-diketones, RC(SH)=CHCOR? (R = R' = Ph; R = Ph, 2-thienyl, ß-naphthyl, R' = CF3), have been prepared by the reaction of chromium(111) chloride hexahydrate with the monothio-ß-diketone in alcohol in the presence of urea. The dipole moments of the chromium chelates were determined by static polarization measurements in benzene solution and indicate a facial-octahedral configuration. The mass spectrum of CrL3 (L = PhC(S)=CHCOPh) shows no metal-containing peaks but exhibits metal-free peaks due to the ions 2L-H2S, 2L - H2S- Ph, 2L- H2S - PhCO and 2L- H2S - PhCO - Ph. The mass spectra of the other three chromium chelates display a considerable number of peaks due to metal-containing ions, including M and M - L. The difference in these spectra from those of their cobalt(111), rhodium(111), iron(111) and ruthenium(111) analogues is discussed.