Details

Autor(en) / Beteiligte

• Siska, Emily
• Smith, Dean
• Childs, Christian
• Koury, Daniel
• Forster, Paul M.
• Lawler, Keith V.
• Salamat, Ashkan

Titel

β -Technetium: An allotrope with a nonstandard volume-pressure relationship

Ist Teil von

• Physical review materials, 2021-06, Vol.5 (6), Article 063603

Ort / Verlag

United States: American Physical Society (APS)

Erscheinungsjahr

2021

Link zum Volltext

Quelle

American Physical Society Journals

Beschreibungen/Notizen

• In this work, we report the synthesis and structure of the second allotrope of technetium, β-Tc. Transformative pathways are accessed at extreme conditions using the laser-heated diamond anvil cell and confirmed with in situ synchrotron x-ray diffraction and Raman spectroscopy. βTc is fully recoverable to ambient conditions, although counter to our DFT calculations predicting a face-centered-cubic lattice, we observe a tetragonal structure (I4/mmm) that exhibits further tetragonal distortion with pressure. β-Tc has an expanded volume relative to the hcp ground state phase, that when doped with nitrogen has an unexpected volume lowering. Such anomalous behavior is possibly indicative of a rare electronic phase transition in a 4d element.