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Updated: Aug 23, 2026

Ammonia Synthesis at Low Pressure
Published on: August 23, 2017
Low temperature pressure broadening of NH3 by D2
Daniel R Willey1, Robert E Timlin, Charles D Ruggiero
1Department of Physics, Allegheny College, Meadville, Pennsylvania 16335, USA. dwilley@allegheny.edu
Abstract:
We report experimentally measured cross sections for pressure broadening of ammonia inversion transitions by J=0, ortho-D2 at temperatures of 18-40 K. These measurements were made in a quasiequilibrium cell using the collisional cooling technique. Cross sections for broadening of the metastable (J,K)=(1, 1), (2, 2) and (3, 3) inversion transitions ranged from 67.5 A2 for (1, 1) at 20.0 K to 100.1 A2 for (3, 3) at 25.0 K. The J=0, ortho-D2 cross sections were found to be consistently larger than previously measured cross sections for low temperature broadening of NH3 by both He and H2.
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