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Vibronic progressions are programmed into a pulse shaper which converts them via the inherent Fourier transformation into a train of femtosecond pulses in time domain for chromophore excitation. Double pulse results agree with phase-sensitive wave packet superposition from a Michelson interferometer which delivers coherence times with high reliability. Spectral resolution of 1 nm and a spacing of around 4 nm within the 20 nm envelope centered at 590 nm delivers a train of seven phase-controlled 40 fs subpulses separated by 250 fs. Combs adjusted to the zero phonon lines (ZPL) and phonon sidebands (PSB) of the B state vibronic progression are reproduced in the chromophore for a coherent subpulse accumulation. B state ZPL wave packet dynamics dominates in pump-probe spectra due to its coherence despite an overwhelming but incoherent A state contribution in absorption. PSB comb accumulation is also phase sensitive and demonstrates coherence within several 100 matrix degrees of freedom in the vicinity.

Photochemical reactions of molecules in solid orthodeuterium (o-D 2 ) have been studied by high-resolution infrared spectroscopy and compared with previous results obtained in solid parahydrogen (p-H 2 ). Ultraviolet photolysis of CD 3 I molecules in solid o-D 2 yielded CD 3 radicals and iodine atoms efficiently, which indicates a small cage effect in solid o-D 2 , as in the case of solid p-H 2 . The Fourier transform infrared spectrum of the v 3 vibrational band of CD 3 showed a rotational structure with additional splitting due to crystal field interactions. The magnetic dipole transition ( 2 P 1/2 - 2 P 3/2 ) of the I atom isolated in solid o-D 2 was observed together with a strong rotational satellite of deuterium molecules through the electron-roton coupling in solid hydrogen. The tunneling reaction between CD 3 and D 2 was not observed in a time scale of a few days, which gives the upper limit of the tunneling reaction rate of 10 -8 s -1 at 4.2 K.