The photofragmentation of propyne-d(3), D3C-C=C-H, following similar to243.1 nm photodissociation of rovibrationally excited molecules promoted to the second (3v(1)) and third (4v(1)) acetylenic C-H overtone and to the third (4v(CD)) methyl overtone has been investigated. The resulting H and D photoproducts were detected via (2 + 1) resonantly enhanced multiphoton ionization. The measured room-temperature photoacoustic and jet-cooled action spectra allowed derivation of the molecular parameters of the C-H overtones and the Doppler profiles revealed the translational energies associated with the H(D) photofragments and the H to D branching ratios. Propensities toward the latter were encountered, while the translational energy disposal in both photofragments was essentially identical for a given preexcitation. This behavior agrees with that found for the almost isoenergetic 193.3 nm photolysis of propyne [Qadiri et al., J. Chem. Phys. 119, 12842 (2003)], but contradicts previous findings. The bond fission of C-H and C-D is preceded by internal conversion to, and isomerization on, the ground-state potential energy surface (PES), followed by extensive intramolecular vibrational redistribution. For molecules preexcited to 3v(1) and 4v(1) an additional minor channel opens, where elimination of H occurs directly on the accessed excited PES, while that of D on the ground state. (C) 2004 American Institute of Physics.