Saved in:
Bibliographic Details
Main Authors: Tan, Yiming, Li, Pai
Format: Preprint
Published: 2026
Subjects:
Online Access:https://arxiv.org/abs/2605.25351
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866910253959872512
author Tan, Yiming
Li, Pai
author_facet Tan, Yiming
Li, Pai
contents Vacancy formation energetics fundamentally govern the structural integrity and catalytic behavior of metal surfaces. Contrary to conventional coordination-dependent broken-bond models, we identify an anomalous thermodynamic inversion on close-packed surfaces across Ir, Pt, Au with face-centered cubic (FCC) lattice and Be, Zn, Cd with hexagonal close-packed (HCP) lattice, where subsurface vacancies are intrinsically more stable than surface ones. Using high-throughput DFT calculations and machine learning force fields, we demonstrate that the physical origins of this anomaly are fundamentally decoupled between the two crystal systems. For the FCC trio, pronounced surface relaxation and a profound real-space electronic localization induce directional, covalent-like intralayer bonding, materializing a "geometry-electronic decoupling" mechanism. Crucially, this unconventional thermodynamic hierarchy enables a dynamic "self-healing" mechanism on Pt(111) that preserves an intact topmost layer and prevents catalytic degradation during hydrogen evolution and oxygen reduction reactions. It also successfully decoding the critical defect threshold (~8%) for lifting the Au(100) surface reconstruction. Our work challenges classical scalar defect models and provides a fresh paradigm for engineering catalyst surface integrity.
format Preprint
id arxiv_https___arxiv_org_abs_2605_25351
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Anomalous Subsurface Vacancy Stabilization Dictated by Geometry-Electronic Decoupling on Metal Surfaces
Tan, Yiming
Li, Pai
Materials Science
Vacancy formation energetics fundamentally govern the structural integrity and catalytic behavior of metal surfaces. Contrary to conventional coordination-dependent broken-bond models, we identify an anomalous thermodynamic inversion on close-packed surfaces across Ir, Pt, Au with face-centered cubic (FCC) lattice and Be, Zn, Cd with hexagonal close-packed (HCP) lattice, where subsurface vacancies are intrinsically more stable than surface ones. Using high-throughput DFT calculations and machine learning force fields, we demonstrate that the physical origins of this anomaly are fundamentally decoupled between the two crystal systems. For the FCC trio, pronounced surface relaxation and a profound real-space electronic localization induce directional, covalent-like intralayer bonding, materializing a "geometry-electronic decoupling" mechanism. Crucially, this unconventional thermodynamic hierarchy enables a dynamic "self-healing" mechanism on Pt(111) that preserves an intact topmost layer and prevents catalytic degradation during hydrogen evolution and oxygen reduction reactions. It also successfully decoding the critical defect threshold (~8%) for lifting the Au(100) surface reconstruction. Our work challenges classical scalar defect models and provides a fresh paradigm for engineering catalyst surface integrity.
title Anomalous Subsurface Vacancy Stabilization Dictated by Geometry-Electronic Decoupling on Metal Surfaces
topic Materials Science
url https://arxiv.org/abs/2605.25351