Sodium–gold binaries: novel structures for ionic compounds from anab initiostructural search

Abstract

Intermetallic compounds made of alkali metals and gold have intriguing electronic and structural properties that have not been extensively explored. We perform a systematic study of the phase diagram of one binary system belonging to this family, namely Na x Au 1−x , using the ab initio minima hopping structural prediction method. We discover that the most stable composition is NaAu 2 , in agreement with available experimental data. We also confirm the crystal structures of NaAu 2 and Na 2 Au, that were fully characterized in experiments, and identify a candidate ground-state structure for the experimental stoichiometry NaAu. Moreover, we obtain three other stoichiometries, namely

Lithiation and Delithiation Mechanisms of Gold Thin Film Model Anodes for Lithium Ion Batteries: Electrochemical Characterization

“…By coupling with ab-initio density functional theory (DFT), this method is capable of predicting stable and metastable crystal structures at a given pressure, from the sole knowledge of the chemical composition of the system. This methodology has shown remarkable results in the prediction of novel structures in a wide range of materials [39][40][41]. We have built the phase diagram for Li-Au, where forty three different stoichiometries starting from pure Li to pure Au were studied.…”

Novel phases of lithium-aluminum binaries from first-principles structural search

“…This method has proved to be able to reproduce experimental results and to find novel structures starting only from the atomic composition of the system. [15][16][17][18][19][20][21] The MHM algorithm, here coupled to DFT, explores the ground-state energy surface by performing short molecular dynamics escape steps followed by local geometry relaxations, taking into account both atomic and cell variables. The initial velocities for the dynamics are aligned preferably along soft-mode directions in order to favor the escape through low barriers to low-enthalpy structures.…”

The Quest for Zero Loss: Unconventional Materials for Plasmonics

“…However, synthesis and characterization of these compounds is challenging and no confirmation of their supposed dielectric functions has been reported yet. Indeed it appears that AuNa does not even exist as a thermodynamically stable phase . The intermetallic compounds in the Cu–Zn system have also been investigated, and their optical properties both calculated and measured with β‐brass identified as having some potential for LSPR‐based applications.…”