The syntheses of C₆CH₂.^– and the corresponding carbenoid cumulene C₆CH₂ in the gas phase

Abstract

The ion (C₆CH₂).^– is formed in the gas phase by the process –C≡C–C≡C–C≡C–CH₂OEt → (C₆CH₂).^– + EtO., and charge stripping of the product radical anion yields the carbenoid neutral C₆CH₂; this can be either a singlet (the ground state), which is best represented as the carbene :C[double bond, length half m-dash]C[double bond, length half m-dash]C[double bond, length half m-dash]C[double bond, length half m-dash]C[double bond, length half m-dash]C[double bond, length half m-dash]CH₂, or a triplet; the adiabatic electron affinity and the dipole moment of the carbenoid neutral are calculated to be 2.82 eV and 7.33 D respectively.

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