Astronomical detection of H2CCC

Abstract

H2CCC, an isomer of the widely distributed interstellar ring C3H2, has been detected in TMC-1 and possibly IRC +10216 with the IRAM 30 m telescope, following a recent laboratory determination of the rotational spectrum of this new type of highly polar carbon chain. The rotational temperature of H2CCC in TMC-1, like that of other highly polar molecules in this source, is very low: 4-6 K; the column density is also fairly low: (2.5 ± 0.5) × 1012 cm-2, slightly more than 1% that of the cyclic isomer. © 1991. The American Astronomical Society. All rights reserved.