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We report laboratory emission spectra of hydrogenated amorphous carbon (HAC) in the wavelength range (525-83 cm Ϫ1) at temperatures between 300ЊC and 500ЊC. These spectra show emission 19 mm ! l ! 120 mm features at 21, 27, and ≈33 mm (475, 370, and 303 cm Ϫ1) that can be identified with similar bands in the farinfrared spectra of extreme carbon stars, proto-planetary nebulae, and planetary nebulae. It is suggested that HAC is present in these objects but that the chemical composition of this material depends on the evolutionary state. We also detect a number of broad features at wavelengths longer than 40 mm, attributable to chemical groups in HAC. A strong feature is observed at ≈60 mm (165 cm Ϫ1) in laboratory spectra and may be present in spectra of the carbon-rich planetary nebula CPD Ϫ56Њ8032. We briefly discuss the nature of the chemical groups responsible for the appearance of these features.

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