Establish the pressure-driven semiconductor-to-metal transition in Fe2TiSi

Establish whether Fe2TiSi undergoes a semiconductor-to-metal phase transition under sufficiently large tensile pressure, particularly below approximately −23 GPa.

Background

The calculated Fe2TiSi band gap decreases under negative pressure and reaches approximately 0.05 eV near −23 GPa. The authors interpret this behavior as evidence that the gap may close at still greater lattice expansion, but the transition is described as possible rather than demonstrated by a calculation showing a fully closed gap and metallic electronic structure.

Confirming the transition would require calculations beyond the reported pressure range or a more detailed characterization of the electronic states after gap closure.