Abstract: The nuclear decay chains beginning with the neutron-deficient isotopes 184Hg, 186Hg, and 188Hg have been studied using isotopically separated sources from the Princeton on-line isotope-separator facility. Ge(Li) and Si(Li) singles spectra and Ge(Li)-Ge(Li) coincidence spectra have been obtained and used in constructing level schemes for the corresponding platinum daughters. Systematics of experimental energy levels and ratios B(E2,2’→2) / B(E2,2’→0) for all known even platinum isotopes are given.