Einstein and Debye Temperatures, Electron-Phonon Coupling Constant and a Probable Mechanism for Ambient-Pressure Room-Temperature Superconductivity in Intercalated Graphite

Recently, Ksenofontov et al. (arXiv:2510.03256) observed ambient pressure room-temperature superconductivity in graphite intercalated with lithium-based alloys with transition temperature (according to magnetization measurements) \( Tₑ =330K \). Here, I analyzed the reported temperature dependent resistivity data \( ρ(T) \) in these graphite-intercalated samples and found that \( ρ(T) \) is well described by the model of two series resistors, where each resistor is described as either an Einstein conductor or a Bloch-Grüneisen conductor. Deduced Einstein and Debye temperatures are \( ΘE,1 ≈ 250~K \) and \( ΘE,2 ≈ 1600~K \), and \( ΘD,1 ≈ 300~K \) and \( ΘD,2 ≈ 2200~K \), respectively. Following the McMillan formalism, from the deduced \( ΘE,2 \) and \( ΘD,2 \), the electron-phonon coupling constant \( λₑ₋ₚₕ ≈ 2.2 \) was obtained. This value of \( λₑ₋ₚₕ \) is approximately equal to the value of \( λₑ₋ₚₕ \) in highly compressed superconducting hydrides. Based on this, I can propose that the observed room-temperature superconductivity in intercalated graphite is localized in nanoscale Sr-Ca-Li metallic flakes/particles, which adopt the phonon spectrum from the surrounding bulk graphite matrix, and as a result, conventional electron-phonon superconductivity arises in these nano-flakes/particles at room temperature. Experimental data reported by Ksenofontov et al. (arXiv:2510.03256) on trapped magnetic flux decay in intercalated graphite samples supports the proposition.