Synthesis of technetium hydride TcH${}_{1.3}$ at 27 GPa

Abstract

In this work, we synthesize and investigate lower technetium hydrides at pressures up to 45 GPa using the synchrotron X-ray diffraction, reflectance spectroscopy, and ab initio calculations. In the Tc-H system, the hydrogen content in TcH${}_x$ phases increases when the pressure rises, and at 27 GPa we found a new hexagonal (hcp) nonstoichiometric hydride TcH${}_{1.3}$. The formation of technetium hydrides is also confirmed by the emergence of a new reflective band at 450-600 nm in the reflectance spectra of TcH${}_x$ samples synthesized at 45 GPa. On the basis of the theoretical analysis, we proposed crystal structures for the TcH${}_{0.45\pm 0.05}$ (Tc${}_{16}$H${}_7$) and TcH${}_{0.75\pm 0.05}$ (Tc${}_4$H${}_3$) phases previously obtained at 1-2 GPa. The calculations of the electron-phonon interaction show that technetium hydrides TcH${}_{1+x}$ do not possess superconducting properties due to the low electron-phonon interaction parameter ($\lambda \sim 0.23$).

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Cited by in corpus (1)

• Discovery of superconductivity in technetium-borides at moderate pressures