The cyanoethynylide ion has been detected toward the carbon rich star IRC +10216 in 4 rotational transitions from J = 10 – 9 to 15 – 14 which occur in the 3 and 2 mm regions:
P. Thaddeus, C. A. Gottlieb, H. Gupta, S. Brünken, M. C. McCarthy, M. Agúndez, M. Guélin, and J. Cernicharo,
Laboratory and Astronomical Detection of the Negative Molecular Ion C<sub>3</sub>N<sup>–</sup>
Astrophys. J. 677, 1132–1139 (2008).
This anion is isolelectronic to C4H–. Besides the presently more common C2nH– family, it is the first member of a second family of anions detected in space, C2n–1N–.
It was searched for, but not found in TMC-1.
Meanwhile,
J. Cernicharo, N. Marcelino, J. R. Pardo, M. Agúndez, B. Tercero, P. de Vicente, C. Cabezas, and C. Bermúdez
reported on
Interstellar nitrile anions: Detection of C<sub>3</sub>N<sup>–</sup> and C<sub>5</sub>N<sup>–</sup> in TMC-1
Astron. Astrophys. 641, Art. No. L9 (2020).
Contributor(s): H. S. P. Müller; 04, 2008; 09, 2020