  We present the first mid-infrared spectra of SMP LMC 11 in the Large
Magellanic Cloud. While this object resembles a planetary nebula in the
optical, its infrared properties are more similar to an object in transition
from the asymptotic giant branch to the planetary nebula phase. A warm dust
continuum dominates the infrared spectrum. The peak emission corresponds to a
mean dust temperature of 330 K. The spectrum shows overlapping molecular
absorption bands from 12 to 17 um corresponding to acetylene and polyacetylenic
chains and benzene. This is the first detection of C4H2, C6H2, C6H6 and other
molecules in an extragalactic object. The infrared spectrum of SMP LMC 11 is
similar in many ways to that of the pre-planetary nebula AFGL 618. The IRS
spectrum shows little evidence of nitrogen-based molecules which are commonly
seen in Galactic AGB stars. Polycyclic aromatic hydrocarbons are also absent
from the spectrum. The detection of the [NeII] 12.8 um line in the infrared and
other forbidden emission lines in the optical indicates that an ionized region
is present.
