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Free Radicals in Superfluid Liquid Helium Nanodroplets: A Pyrolysis Source for the Production of Propargyl Radical

Jochen Küpper·Jeremy M. Merritt·Roger E. Miller
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Abstract

An effusive pyrolysis source is described for generating a continuous beam of radicals under conditions appropriate for the helium droplet pick-up method. Rotationally resolved spectra are reported for the $ν_1$ vibrational mode of the propargyl radical in helium droplets at 3322.15 cm$^{-1}$. Stark spectra are also recorded that allow for the first experimental determination of the permanent electric dipole moment of propargyl, namely -0.150 D and -0.148 D for ground and excited state, respectively, in good agreement with previously reported ab initio results of -0.14 D [1]. The infrared spectrum of the $ν_1$ mode of propargyl-bromide is also reported. The future application of these methods for the production of novel radical clusters is discussed.

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Jochen Küpper, Jeremy M. Merritt, Roger E. Miller. 2006-08-08. Free Radicals in Superfluid Liquid Helium Nanodroplets: A Pyrolysis Source for the Production of Propargyl Radical. https://doi.org/10.1063/1.1484104

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