infrared multiphoton dissociation spectroscopy resonant infrared multiphoton dissociation spectroscopy IR REMPD IR REMPD spectrometry IR REMPD spectroscopy CHMO:0000634 resonant infra-red multiphoton dissociation spectroscopy resonance-enhanced infrared multiphoton dissociation spectroscopy resonant infrared multiphoton dissociation spectrometry resonant infra-red multiphoton dissociation spectrometry resonance-enhanced infrared multiphoton dissociation spectrometry IR-REMPD Spectroscopy where the sample absorbs resonant radiation from the infrared region (0.78–1000 μm) with sufficient energy to cause photodissociation by the absorption of two or more photons.