Abstract
Two hydrogenated intermetallics with the highest Al/Zr ratio among the hydrogen-absorbing Zr–Al compounds, Zr4Al3 and Zr3Al2, have been studied by synchrotron X-ray, powder neutron diffraction and thermal desorption spectroscopy. Initial intermetallic compounds are quite different with respect to Al–Al interactions and contain plain Kagome Al nets (Zr4Al3) or Al–Al pairs (Zr3Al2). In hexagonal Zr4Al3D2.68 (space group (s.g.) P6322; a=11.0017(4); c=11.1694(5) Å) a 2a×2a×2c superstructure is formed as a result of deuterium ordering in half of the available Zr4 tetrahedra. These tetrahedra share common corners and edges and form layers separated by 6363 Al-nets. In tetragonal Zr3Al2D2.26 (s.g. P42/mnm; a=7.5970(3); c=7.2613(3) Å) in addition to the completely filled Zr4 tetrahedra hydrogen partially occupies Zr3 triangular sites. Thermal stability of the studied deuterides and Zr–D bonding characteristics can be related to the size of the occupied Zr4 tetrahedra. Higher thermal stability of Zr3Al2D2.26 agrees well with the existence of large Zr4 sites and contrasts to the behavior of Zr4Al3D2.68 containing ‘contracted’ Zr4 tetrahedra and having weaker Zr–D bonds.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
