By using Fourier-Transform Infrared (FTIR) absorption spectroscopy, rate coefficients in the range of 10(-16) to 10(-14) cm(3) molecule(-1) s(-1) have been determined for the hydrogen atom abstraction reactions of several substrates including halogenated organic compounds and amines by t-butoxy radical generated from the uv photolysis of t-butyl nitrite in the gas phase. Arrhenius parameters for selected reactions have been measured in the temperature range 299-318 K. Transition states and activation barriers for such reactions have been computed with the help of GAUSSIAN 03 software and found to match very well with the experimental values. (c) 2006 Elsevier B.V. All rights reserved.