The rate constantkafor electron attachment to F2has been measured at ambient (298 K) temperatureTin the buffer gas Ar over the mean electron energy lang;egr;rang; range 0.40ndash;2.95 eV; similar measurements were made atT=233, 298, and 373 K in the buffer gas N2over the lang;egr;rang; range 0.04ndash;0.75 eV. Theka(lang;egr;rang;) function attains a maximum value of 1.7times;10minus;8cm3thinsp;sminus;1(T=298 K) at sim;0.04 eV and decreases monotonically with increasing lang;egr;rang; above thermal energy; the magnitude ofkaincreases only slightly with increasingT. Theka(lang;egr;rang;) data at 298 K were unfolded and the resultant cross section sgr;a(egr;) shows a main maximum at sim;0.0 eV, a shoulder at sim;0.5 eV, and a weak maximum at sim;1.1 eV. Possible electron attachment processes are discussed to account for the energy dependence of sgr;a(egr;). Also discussed, in the light of the present measurements, are published experimental and theoretical results onka(lang;egr;rang;) and sgr;a(egr;).
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