Volume 34, Issue 4 (July 1989)
Variations in the Infrared Spectra of Heroin Base
The infrared spectrum of the heroin base standard supplied with the Georgia State Crime Laboratory (GSCL) library index has a carbonyl doublet with absorbance maxima at 1756.6 and 1728.3 cm−1. Most heroin base samples from actual cases have carbonyl absorbance maxima at 1761.3 and 1741.1 cm−1 with additional differences in the spectra at 2800 to 3200 cm−1 and in the fingerprint region. These differences could not be accounted for as a result of impurities, decomposition products, additives, or diluents. At least two polymorphic forms of heroin base exist with various crystal habits. The main parameters determining which polymorph and crystal habit are obtained are the temperature conditions and solvent used for crystallization.