Yttrium hydride

General
Surname	Yttrium hydride
other names	Yttrium trihydride
Molecular formula	YH 3
Brief description	yellow solid
External identifiers / databases
CAS number 13598-57-7 EC number 237-074-0 ECHA InfoCard 100,033,689 PubChem 166870 Wikidata Q21051460
properties
Molar mass	91.93 g mol −1
Physical state	firmly
density	3.94 g cm −3 4.13 g cm −3 (yttrium trideuteride)
Melting point	300 ° C (decomposition)
safety instructions
GHS hazard labeling no classification available
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Yttrium hydride (more precisely yttrium trihydride) is a chemical compound of yttrium from the group of hydrides . In addition, another hydride is known with yttrium dihydride.

Extraction and presentation

Yttrium hydride can be obtained by reacting yttrium dihydride with hydrogen .

properties

Yttrium hydride is a yellow solid. It decomposes above 300 ° C.

It has a hexagonal crystal structure with the space group P 6 ₃ cm (space group no. 185) . There is also a modification with the space group Fm 3 m (No. 225) .

use

While yttrium and yttrium dihydride have a metallic character and reflect visible light, yttrium trihydride is optically transparent in a thin layer. Under suitable conditions, a transition between these two connections takes place within fractions of a second, so that this process is abrupt for the human eye. The reversibility of this effect makes it interesting for technological applications such as mirrors or glasses. Since the hydrogen-induced optical switching has so far only been observed in thin layers, but not in volume samples, it is conceivable that the optical transparency is a property of thin layers. Yttrium trihydride has also been studied for use as a moderator in nuclear reactors.

Individual evidence

1. ^ ^{A b c d} Andreas Züttel, Andreas Borgschulte, Louis Schlapbach: Hydrogen as a Future Energy Carrier . John Wiley & Sons, 2011, ISBN 3-527-62290-X , p. 299.
2. ^ ^{A b} William M. Mueller, James P. Blackledge, George G. Libowitz: Metal Hydrides . Elsevier, 2013, ISBN 978-1-4832-7293-1 ( limited preview in Google Book Search).
3. ↑ This substance has either not yet been classified with regard to its hazardousness or a reliable and citable source has not yet been found.
4. ^ William M. Mueller, James P. Blackledge, George G. Libowitz: Metal Hydrides . Elsevier, 2013, ISBN 978-1-4832-7293-1 , pp. 450 ( limited preview in Google Book Search).
5. ^ William M. Mueller, James P. Blackledge, George G. Libowitz: Metal Hydrides. Elsevier, 2013, ISBN 978-1-4832-7293-1 , p. 443 ( limited preview in Google book search).
6. ↑ Ana Maria Racu: Micro-Raman spectroscopy study of ordering phenomena in YH _x thin films and in CuTe ₂ O ₅ single crystals. Cuvillier Verlag, 2005, ISBN 978-3-86537-567-4 , p. 36 ( limited preview in Google book search).
7. ↑ Laboratory 67: Hydrogen Materials Science and Chemistry of Carbon Nanomaterials Ichms 2005. Laboratory 67, p. 228 ( limited preview in the Google book search).
8. ↑ R. Griessen: Switchable mirrors made of metal hydrides. In: Physics Journal. 53, 1997, p. 1207, doi: 10.1002 / phbl.19970531210 .
9. ↑ Remhof, Arndt: hydrogen in yttrium films: structure and phase formation. Dissertation, Ruhr University Bochum, 2000 urn : nbn: de: hbz: 294-372 ( abstract ).
10. ^ William M. Mueller, James P. Blackledge, George G. Libowitz: Metal Hydrides . Elsevier, 2013, ISBN 978-1-4832-7293-1 , pp. 442 ( limited preview in Google Book search).