*Glyoxal

1) UV/vis absorption cross section of Glyoxal at 296K

Experimental conditions:

- Mixtures of glyoxal and N₂.

- Static mode, pressure:  range 0.4 to 13.4 mbar of glyoxal in 1 atm N₂.

- Room temperature: 296K

Spectroscopic conditions

- Analysis light source: Xenon arc lamp(UV-VIS) / globar lamp (IR).

- Detection system:

- Fourier Transform Spectrometer (Brucker IFS-120 HR)

- Resolution: 0.001nm, 0.01nm, 0.1nm and 1nm FWHM

- Reaction vessel: glass, 83.5 cm, multi path optics (White type), mirrors: Al, path length 1.64 cm

Analysis

-Amount of glyoxal determined by converting pressure variation in an empty vessel into concentration. 1 atm N₂ was added after pressure variation measurement.

-Cell leak rate and glyoxal losses were characterised and the glyoxal pressure was accordingly corrected

-Lamp drift characterised and corrected.

-the combination of all remaining error sources yields an overall error which is 5% or better, but not less than 2×10^-22 cm²/molec.

Absolute scaling

            -by direct measurement of pressure (see "Analysis" above).

UV-Vis Data (250 - 526nm):

0.001nm FWHM

                        ASCII DATA: glyoxal_0.001nmFWHM_IUP.zip

FIGURE : glyoxal_0.001nmFWHM_IUP.jpg

            0.01nm FWHM:

ASCII DATA: glyoxal_0.01nmFWHM_IUP.zip

FIGURE : glyoxal_0.01nmFWHM_IUP.jpg

            0.1nm FWHM:

ASCII DATA: glyoxal_0.1nmFWHM_IUP.zip

FIGURE : glyoxal_0.1nmFWHM_IUP.jpg

            1.0nm FWHM:

ASCII DATA: glyoxal_1.0nmFWHM_IUP.zip

FIGURE : glyoxal_1.0nmFWHM_IUP.jpg

IR Data (2500-3000cm^-1):

            0.009cm^-1FWHM:

ASCII DATA: Glyoxal_IR_0.009cmFWHM_IUP.zip

FIGURE (in 1 mbar N₂): Glyoxal_IR_0.009cmFWHM_1mbar_IUP.png

FIGURE (in 100 mbar N₂): Glyoxal_IR_0.009cmFWHM_100mbar_IUP.png

FIGURE (in 300 mbar N₂): Glyoxal_IR_0.009cmFWHM_300mbar_IUP.png

FIGURE (in 1000 mbar N₂): Glyoxal_IR_0.009cmFWHM_1000mbar_IUP.png

Published: Volkamer R; Spietz P; Burrows J; Platt U.; High-resolution absorption cross-section of Glyoxal in the UV/vis and IR spectral ranges, J. Photochem. Photobiol. (2005) 172, 35. DOI: 10.1016/j.jphotochem.2004.11.011