In 1993, the [Pt(CO)₄]²⁺ ion was reported for the first time [G. Hwang et al. (1993) Inorg. Chem., vol. 32, p. 4667]. One strong absorption at 2235 cm^–1 in the IR spectrum was assigned to ν_CO, and this was absent in the Raman spectrum. In the Raman spectrum, two absorptions (ν_CO) at 2257 and 2281 cm^–1 (absent in the IR spectrum) were observed. Show that these data are consistent with [Pt(CO)₄]²⁺ having D_4h symmetry.