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.

Neutron Scattering Investigations of the Global and Local Structures of Ammine Yttrium Borohydrides

Published

Author(s)

Jakob Grinderslev, Mikael S. Andersson, Benjamin Trump, Wei Zhou, Terrence J. Udovic, Maths Karlsson, Torben Jensen

Abstract

Complex metal hydrides are a fascinating and continuously expanding class of materials with many properties relevant for solid-state hydrogen and ammonia storage and solid state electrolytes. The crystal structures are often investigated using powder X-ray diffraction (PXD), which can be ambiguous. Here we revisit the crystal structure of Y(11BD4)3∙3ND3 with the use of neutron diffraction, which, in comparison to previous PXD studies, provides accurate information about the D positions in the compound. Upon cooling to 10 K, the compound underwent a polymorphic transition, and a new monoclinic low-temperature polymorph denoted as α-Y(11BD4)3∙3ND3 was discovered. Furthermore, the series of Y(11BH4)3∙xNH3 (x = 0, 3 and 7) were also investigated with inelastic neutron scattering and infrared spectroscopy techniques, which provided information of the local coordination environment of the 11BH4- and NH3 groups as well as unique insight into the hydrogen dynamics. Partial deuteration using ND3 in Y(11BH4)3∙xND3 (x = 3 and 7) allowed for an unambiguous assignment of the vibrational bands corresponding to the NH3 and 11BH4- in Y(11BH4)3∙xNH3, due to the much larger neutron scattering cross section of H compared to D. The vibrational spectra of Y(11BH4)3∙xNH3 could roughly be divided into three regions: i) below 55 meV, containing mainly 11BH4- librational motions, ii) 55 - 130 meV, containing mainly NH3 librational motions and iii) above 130 meV, containing 11B-H and N-H bending and stretching motions.
Citation
Journal of Physical Chemistry C
Volume
125
Issue
28

Keywords

ammine yttrium borohydrides, crystal structures, inelastic neutron scattering, neutron powder diffraction, neutron vibrational spectroscopy, x-ray diffraction, Y(BH4)3, yttrium borohydride

Citation

Grinderslev, J. , Andersson, M. , Trump, B. , Zhou, W. , Udovic, T. , Karlsson, M. and Jensen, T. (2021), Neutron Scattering Investigations of the Global and Local Structures of Ammine Yttrium Borohydrides, Journal of Physical Chemistry C (Accessed May 29, 2024)

Issues

If you have any questions about this publication or are having problems accessing it, please contact reflib@nist.gov.

Created July 21, 2021, Updated November 29, 2022