The Physical State of Clusters. An Infra-red Laser Study of Small Cyclopropane and Dimethylcyclopropane Clusters

Infrared absorption profiles have been measured for cyclopropane and 1,1-dimethylcyclopropane clusters by monitoring the depletion of signal intensity in a mass spectrometer as a function of laser wavelength. Data have been obtained for (C₃H₆)n⁺ with n in the range 2–15, and for (C₅H₁₀)n⁺ with n equal to 2 and 5. A comparison between the cluster results and available infrared data on the various bulk-phase states of both cyclopropane and 1,1-dimethylcyclopropane, suggests that the clusters are liquid-like.