TY  - JOUR
AU  - Serghiou, George
AU  - Odling, Nicholas
AU  - Reichmann, Hans Josef
AU  - Spektor, Kristina
AU  - Crichton, Wilson A.
AU  - Garbarino, Gaston
AU  - Mezouar, Mohamed
AU  - Pakhomova, Anna
TI  - Unconventional Route to High-Pressure and -Temperature Synthesis of GeSn Solid Solutions
JO  - Journal of the American Chemical Society
VL  - 143
IS  - 21
SN  - 1520-5126
CY  - Washington, DC
PB  - American Chemical Society
M1  - PUBDB-2021-02561
SP  - 7920 - 7924
PY  - 2021
AB  - Ge and Sn are unreactive at ambient conditions. Their significant promise for optoelectronic applications is thus largely confined to thin film investigations. We sought to remove barriers to reactivity here by accessing a unique pressure, 10 GPa, where the two elements can adopt the same crystal structure (tetragonal, I4<sub>1</sub>/amd) and exhibit compatible atomic radii. The route to GeSn solid solution, however, even under these directed conditions, is different. Reaction upon heating at 10 GPa occurs between unlike crystal structures (Ge, Fd3m and Sn, I4/mmm), which also have highly incompatible atomic radii. They should not react, but they do. A reconstructive transformation of I4/mmm into the I4<sub>1</sub>/amd solid solution then follows. The new tetragonal GeSn solid solution (I4<sub>1</sub>/amda = 5.280(1) Å, c = 2.915(1) Å, Z = 4 at 9.9 GPa and 298 K) also constitutes the structural and electronic bridge between 4-fold and newly prepared 8-fold coordinated alloy cubic symmetries. Furthermore, using this high-pressure route, bulk cubic diamond-structured GeSn alloys can now be obtained at ambient pressure. The findings here remove confining conventional criteria on routes to synthesis. This opens innovative avenues to advanced materials development.
LB  - PUB:(DE-HGF)16
C6  - pmid:34008965
UR  - <Go to ISI:>//WOS:000659443000007
DO  - DOI:10.1021/jacs.1c03765
UR  - https://bib-pubdb1.desy.de/record/459416
ER  -