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arXiv · 2401.06319

Bain distortion of noble metal thin films that exhibit fcc, bct, and reoriented fcc structures

Shota Ono·Koharu Tamura
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Abstract

A recent experiment has reported that body-centered cubic (bcc)-structured Ag is realized by bending face-centered cubic (fcc)-structured Ag nanowires [S. Sun {\it et al}., Phys. Rev. Lett. {\bf 128}, 015701 (2022)]. However, the bcc phase has been observed only near the Ag surface. Here, we explore how the bcc phase is stabilized near the surface by compressions. Our first-principles calculations for noble metals, Cu, Ag, and Au, indicate that body-centered tetragonal (bct) rather than bcc structure is preferred due to the surface effect. The bct-fcc boundary treated as a fixed boundary condition is necessary to thermodynamically stabilize the bct phase of Ag nanowire. The correlation between crystal structure and electron density-of-states is also discussed for three noble metals.

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Shota Ono, Koharu Tamura. 2024-01-12. Bain distortion of noble metal thin films that exhibit fcc, bct, and reoriented fcc structures. https://arxiv.org/abs/2401.06319

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