Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Reorientational Dynamics of the Dodecahydro-Closo-Codecaborate Anion in Cs2B12H12



Kristina Verdal, Terrence J. Udovic, John J. Rush, Ronald L. Cappelletti, Wei Zhou


Rapid reorientational motions of the B12H122- icosahedral anion, a key intermediate in borohydride dehydrogenation, are revealed by quasielastic neutron scattering (QENS) measurements of Cs2B12H12 between 430 K and 530 K. At 430 K, over the range of momentum transfers collected, the elastic incoherent structure factor is consistent with a model for reorientation about a single molecular axis. At temperatures of 480 K and higher, however, the reorientation seems to proceed by dynamically similar, independent jumps about two axes: the three-fold and five-fold rotational axes, preserving crystallographic order. Although neutron vibrational spectra demonstrate that the anion torsional modes soften dramatically with increasing temperature, the QENS-derived activation energy for reorientation clearly shows that the anions are not undergoing random rotational diffusion.
Journal of Physical Chemistry Letters


hydrogen storage, B12H12, quasielastic neutron scattering, hydrogen dynamics


, K. , Udovic, T. , Kasianowicz, J. , Cappelletti, R. and Zhou, W. (2011), Reorientational Dynamics of the Dodecahydro-Closo-Codecaborate Anion in Cs<sub>2</sub>B<sub>12</sub>H<sub>12</sub>, Journal of Physical Chemistry Letters, [online], (Accessed April 12, 2024)
Created March 17, 2011, Updated February 19, 2017