Revealing an unusual transparent phase of superhard iron tetraboride under high pressure.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 25404295.
- Also identified by DOI 10.1073/pnas.1419244111 and PMC identifier 4260608.
- No licence information is recorded for this record.
- Because redistribution is not established, this page shows the abstract only. Follow the links below for the full text.
Abstract
First principles-based electronic structure calculations of superhard iron tetraboride (FeB4) under high pressure have been undertaken in this study. Starting with a "conventional" superconducting phase of this material under high pressure leads to an unexpected phase transition toward a semiconducting one. This transition occurred at 53.7 GPa, and this pressure acts as a demarcation between two distinct crystal symmetries, metallic orthorhombic and semiconducting tetragonal phases, with Pnnm and I4₁/acd space groups, respectively. In this work, the electron-phonon coupling-derived superconducting T(c) has been determined up to 60 GPa and along with optical band gap variation with increasing pressure up to 300 GPa. The dynamic stability has been confirmed by phonon dispersion calculations throughout this study.