Quenching of Electronically Excited NF

Quenching of NF(b) by various reagents was studied [1] in the flowing afterglow of the Ar( Po,2) + NF2 reaction by measuring the decay of the NF(b X) emission intensity I(b X) which is proportional to the concentration of NF(b). The decay of NF(b) was assumed to consist of radiative decay, wall deactivation, and quenching by the Ar carrier gas, by the NF2 precursor, and by the added reagents Q  

In a study of the radiative decay of NF(b) generated in the Ar( Po,2) + NF3 reaction, the quenching rate constants for Ar and NF3 were measured [2]. The value for k Pg was larger by a factor of about 300 than that found later [1]. The discrepancy was attributed to impurities [2] in the NF3 gas. 

The short-lived ultraviolet absorption bands having NF(b) (or NF(a), cf. p. 287) in the lower state were removed by collisions with N2,02, or NF2 at 450 K. Upper limits for k gand ko and an approximate value for kNp were thereby derived [5] (assignment to NF(b) also in [6]). 

NF(b Quenching Rate Constants kq in 10 cm -molecule -s at 300 K. Results are from [1] if no other reference is given. 

A near-resonant E-E transfer between NF(b) (generated in the F + HN3 reaction) and ground state IF (formed rapidly upon adding I2 or CF3I into the flow tube), that is, NF(b 2 ) + IF(X 2 )- NF(X 32 ) IF(B 3n(0 ))-49 cm was found to occur at a near gas kinetic rate. From the ratio of the IF(B- X) and NF(b- X) intensities plotted versus the partial pressures of the added I2 or CF3I, a lower limit was derived for the rate constant, k p 1.8x10 Torr s [7]. 

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