134451-24-4Relevant academic research and scientific papers
The libration-vibration bands of the ammonium ion in ammonium tetraphenylborate: Evidence for nearly free rotation
Roberts, Malcolm P.,Clavell-Grunbaum, Dolores,Strauss, Herbert L.
, p. 6393 - 6405 (1987)
The N-H stretching and H-N-H bending regions of the infrared spectrum of the title compound (ATPB) have been examined with care. The stretching bands show rotation-like structure that we attribute to rotational motion of NH 4+ in a very low barrier. The barrier has the symmetry of a tetrahedral molecule in a tetrahedral site and is characterized by the dimensionless parameter β=1. The J=0 and J=1 levels are below the barrier and the J=2 levels are above it. Slow interconversion of nuclear spin species is seen in keeping with the low barrier model. The spectra of the ATPB with some NH3D+, with a high concentration of K+ and with deuterated phenyl groups have been examined, and show spectra in keeping with the model.
