Experimental and Theoretical Study of the Kinetics of Dimerization of Ammonia at Low Temperatures.

ABSTRACT: The kinetics of the dimerization of NH₃ in helium and nitrogen bath gas within the supersonic flow of a Laval nozzle were investigated at very low temperatures. Experimentally, the fraction of the NH₃ monomer, f_monomer, remaining in the flow at 91 K in N₂ and at 35 K in He for a total bath gas density [M]∼5 × 10¹⁶ molecules cm^-3 was monitored using fluorescence from the electronically excited NH₂ photofragment formed following NH₃ photolysis at 213 nm. No dimerization was observed up to [NH₃] = 1 × 10¹⁵ molecules cm^-3 for 160 mm downstream of the 91 K N₂ nozzle, nor up to [NH₃] = 5 × 10¹⁴ molecules cm^-3 for 150 mm downst

SUBMITTER: Li LHD 

PROVIDER: S-EPMC12278223 | biostudies-literature | 2025 Jul

REPOSITORIES: biostudies-literature