@article{1538-4357-509-2-L141,
  author={C. A. Gottlieb and M. C. McCarthy and V. D. Gordon and J. M. Chakan and A. J. Apponi and P. Thaddeus},
  title={Laboratory Detection of Two New C5H2 Isomers},
  journal={The Astrophysical Journal Letters},
  volume={509},
  number={2},
  pages={L141},
  url={http://stacks.iop.org/1538-4357/509/i=2/a=L141},
  year={1998},
  abstract={Two new isomers of the C 5 H 2 molecule have been detected in the laboratory, and their microwave spectra have been characterized to high accuracy. Both are good candidates for radio astronomical detection. Like the two isomers previously detected in the laboratory, both are closed-shell carbenes, and both are extremely polar and fairly stable. The first, calculated to lie 0.73 eV above isomer 1, the C 5 H 2 ring-chain ground state, has a bent carbon chain backbone with single, double, and triple bonds; the second, calculated to lie only 0.19 eV higher in energy, is a new type of ring chain formed by adding a pair of doubly bonded carbon atoms to the top of the C 3 H 2 ring, which is one of the most abundant interstellar molecules.}
}