The discovery of superconductivity approaching room temperature in hydrogen-rich compounds under extreme pressure has firmly established phonon-mediated pairing as a viable route to very high critical temperatures. However, the requirement of megabar pressures remains a fundamental obstacle to technological application. In this work, I present a comprehensive first-principles investigation of Li₂AuH₆, a ternary hydride stable at ambient pressure, and demonstrate that strain engineering and dimensional reduction can drive this compound to the threshold of room-temperature superconductivity at zero external pressure. Using density-functional theory (DFT), density-functional perturbation theory (DFPT), and Migdal–Eliashberg theory, I show that biaxial tensile strain in a Li₂AuH₆ monolayer enhances the electronic density of states at the Fermi level and selectively softens hydrogen-dominated phonon modes without inducing structural instabilities. The resulting electron–phonon coupling constant reaches λ ≈ 2.4–2.6 while maintaining an exceptionally high logarithmic phonon frequency 𝜔𝑙𝑜𝑔≈ 1900–2000 K. These parameters yield a predicted superconducting transition temperature Tc in the range 280–320 K within the Allen–Dynes formalism. I analyze the microscopic origin of this enhancement, quantify anharmonic effects, and outline realistic experimental pathways for synthesis and verification. My results identify Li₂AuH₆ as one of the most credible candidates currently known for achieving superconductivity near room temperature at ambient pressure within established physical theory.
Giustino Travaglini (Fri,) studied this question.