Temperature dependence of absorption cross-section of H2O, HOD, and D2O inthe spectral region 140-193 nm

Measurements of absolute photoabsorption cross-sections of H2O, D2O and HOD in the spectral range 140-195 nm were performed at 295, 275, and 250 K usi ng a double-beam absorption cell with a synchrotron radiation source. The a bsorption cross-sections in the spectral range 150-174 nm are nearly invari ant upon isotopic substitution, but become smaller for heavier isotopomers in the region lambda > 174 nm. For each isotopomer, absorption cross-sectio ns are nearly temperature independent in the spectral range 140-173 nm, but exhibit a small negative temperature dependence for wavelengths greater th an 173 nm. (C) 2001 Elsevier Science B.V. All rights reserved.