Two-photon dissociation of NO near 275 nm investigated by velocity map imaging

The two-photon dissociation of NO at wavelengths near 275 nm has been investigated by velocity map imaging of the O(P-3(2)) dissociation product. Two channels are seen, corresponding to formation of the co-product N atoms in their ground (S-4) and excited (D-2) states, and the relative yields and angular distributions measured. In their regions of maximum yield, the channel forming N(D-2) produces unaligned products, whereas that producing N(S-4) can be described by a beta value of ca. 0.4. N(D-2)/N(S-4) ratios vary by a factor of 60 over a narrow range of excitation energies. The use of two-photon excitation of NO as a source of aligned atoms for reaction stereodynamics is discussed. (C) 1998 Published by Elsevier Science B.V. All rights reserved.