Nessler, W.; Bornscheuer, K.h; Kolasinski, K.w.; Hasselbrink, Eckart:

Quantum State-resolved Study of NH₃ Photodesorbed from GaAs(1 0 0).

In: Nuclear Instruments & Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms (Nucl Instrum Methods Phys Res Sect B), Jg. 101 (1995) ; Nr. 1,2, S. 49-52
Zeitschriftenaufsatz / Fach: Chemie
The laser-induced desorption of ammonia from GaAs(1 0 0)-(4*6) has been studied using (2+1)-photon REMPI as a state-specific probe. Ammonia and its deuterated sibling exhibit surprisingly large isotope effects in their relative cross sections for photodesorption from GaAs. This finding has led to the proposition of a vibrationally mediated UV photodesorption model. We find that NH₃ desorbs with a mean translational energy, {Etrans}, of 300 K, a rotational temp. of about 520 K, and vibrational excitation in the ν₂ mode corresponding to about 930 K.