Vacuum ultraviolet spectrum of dinitrogen pentoxide

Absolute photoabsorption cross-sections at 195 +/- 3 K are reported for dinitrogen pentoxide, N2O5, between 150 and 240 nm. The spectrum consists of a broad intense band with a maximum at 160 nm. The lack of sharp features indicates that excitation of N2O5 results in dissociation over the whole of the spectral range studied. At wavelengths above 200 nm, our results are up to 30% smaller than the current NASA recommendation, but are in generally good agreement with a more recent measurement. Below 200 nm, there are no reported data with which to compare our work. (C) 1999 Elsevier Science Ltd. All rights reserved.