HBM-Diamonoid Phase

HBM-Diamondoid Phase — A Hypothetical Ambient-Pressure High-Tc Superconducting Diamondoid Material I'm pleased to submit my manuscript entitled: “HBM-Diamondoid Phase: A Hydrogenated Boron–Magnesium Diamondoid Architecture for Potential High-Temperature Superconductivity at Ambient Pressure”. In this work, I propose a previously unreported multicomponent diamondoid material architecture based on the explicit structural formula: Li₂Mg₄C₃₄ (BC₄H₁. ₅) ₈ The proposed phase combines four key physical concepts that have independently emerged in modern superconductivity research, yet have not previously been unified within a single covalent framework: Diamond-like sp³ carbon rigidity, providing an ultrahigh Debye scale and exceptional lattice stability; Ordered boron subnetworks, inspired by σ-band superconductivity in MgB₂-type systems; Structural hydrogen incorporation through B–H–C bridging motifs, generating ultrahigh-frequency optical phonon modes without requiring megabar pressures; Metallic charge donation via Li/Mg channels, enabling multiband metallicity while preserving covalent integrity. The resulting architecture constitutes a hybrid covalent metamaterial positioned conceptually between borides, diamond-derived superconductors, and hydrogen-rich high-Tc systems. Using a physically motivated theoretical framework based on density-functional considerations and anisotropic Migdal–Eliashberg phenomenology, I identify several remarkable emergent characteristics: • Dynamically stable diamondoid backbone with ordered B–C subnetworks;• Strong electron–phonon coupling mediated by B–H and C–H stretching modes;• High logarithmic phonon frequencies (ωₗog ≈ 1400 K) ;• Estimated electron–phonon coupling parameter λ ≈ 1. 5–1. 8;• Predicted superconducting critical temperatures potentially exceeding 100 K at ambient pressure, with optimistic regimes approaching ~200 K. Importantly, the proposed material does not rely on extreme compression, distinguishing it fundamentally from conventional hydride superconductors operating above 100 GPa. I believe this work may open a new conceptual pathway toward ambient-pressure superconductivity by integrating ultrarigid covalent frameworks with hydrogen-enhanced phononic architectures. Beyond superconductivity, the proposed phase may also stimulate broader exploration of metastable diamondoid quantum materials combining light-element chemistry, multiband metallicity, and engineered phonon spectra. I believe the interdisciplinary nature of this work — spanning superconductivity, quantum materials, phonon engineering, and metastable covalent solids — makes it highly suitable for a broad readership in advanced materials physics.