The planar platinum(II) complex [Pt(Me₃SiCCbpyCCSiMe₃)(CCC₆H₄Et-4)₂] (1) with 5,5-bis(trimethylsilylethynyl)-2,2′-bipyridine was prepared and characterized. Solid-state 1 exhibits unusual, selective and reversible luminescence vapochromism to CH₃CN and ClCH₂CN vapors, which is useful for the detection of these hazardous vapors. A vapochromic cycle was monitored by dynamic variations in emission spectra and X-ray diffraction (XRD) patterns. Both X-ray crystallographic and density functional theory studies suggest that the vapochromic and vapoluminescent behavior of 1 are induced by the variation in the intermolecular Pt–Pt interactions.