β -Technetium: An Allotrope With a Nonstandard Volume-Pressure Relationship

Authors

Emily Siska, University of Nevada, Las VegasFollow
Dean Smith, Argonne National Laboratory
Christian Childs, University of Nevada, Las Vegas
Daniel Koury, University of Nevada, Las VegasFollow
Paul M. Forster, University of Nevada, Las VegasFollow
Keith V. Lawler, University of Nevada, Las VegasFollow
Ashkan Salamat, University of Nevada, Las VegasFollow

Document Type

Article

Publication Date

6-9-2021

Publication Title

Physical Review Materials

Volume

5

Issue

6

First page number:

1

Last page number:

7

Abstract

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. β-Tc 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.

Disciplines

Physical Chemistry | Physics

File Format

pdf

File Size

1632 KB

Language

English

Rights

IN COPYRIGHT. For more information about this rights statement, please visit http://rightsstatements.org/vocab/InC/1.0/

Repository Citation

Siska, E., Smith, D., Childs, C., Koury, D., Forster, P., Lawler, K., Salamat, A. (2021). β -Technetium: An Allotrope With a Nonstandard Volume-Pressure Relationship. Physical Review Materials, 5(6), 1-7.
http://dx.doi.org/10.1103/PhysRevMaterials.5.063603