The possibility of reactive scattering resonances in collinear (H-, H-
2) collisions is examined by computing the transition state spectra ob
tained by Fourier transforming temporal autocorrelation functions for
wavepackets placed initially in the transition state region of the ab
initio potential energy surface for the system. The nature of the reso
nances is investigated by computing the corresponding eigenfunctions a
nd their lifetimes.