Unconventional Route to High-Pressure and -Temperature Synthesis of GeSn Solid Solutions

Ge and Sn are unreactive at ambient conditions. Their significant promise for optoelectronic applications is thus largely confined to thin film investigations. We sought remove barriers reactivity here by accessing a unique pressure, 10 GPa, where the two elements can adopt same crystal structure (tetragonal, I41/amd) exhibit compatible atomic radii. The route GeSn solid solution, however, even under these directed conditions, different. Reaction upon heating GPa occurs between unlike structures (Ge, Fd3m Sn, I4/mmm), which also have highly incompatible They should not react, but they do. A reconstructive transformation of I4/mmm into I41/amd solution then follows. new tetragonal (I41/amd = 5.280(1) Å, c 2.915(1) Z 4 9.9 298 K) constitutes structural electronic bridge 4-fold newly prepared 8-fold coordinated alloy cubic symmetries. Furthermore, using this high-pressure route, bulk diamond-structured alloys now be obtained pressure. findings confining conventional criteria on routes synthesis. This opens innovative avenues advanced materials development.