Is There a Sea of Free Electrons in Metals?

Challenges regarding the widely accepted BCS superconductivity theory may arise from misconceptions about the sea of free-moving electrons and metallic bonds. Based on these concepts, electrical resistance is assumed to be caused by electron vibrations and collisions in conductors. Implicitly granted by this model, the BCS theory suggests that coupled electrons in Cooper pairs can minimize their vibrations and resistance, leading to the phenomenon of superconductivity. However, if delocalized electrons were responsible for holding molecules together in metallic bonds, how could metal structures remain stable when electrons move in a current? The primary challenge to these models is the negative impact of pressure on resistivity and superconductivity. Abandoning these models, an alternative theory introduces the concept of isopotential electron tunnels within conductors. Formed between closely spaced molecules, these tunnels allow electrons to move across molecules at the same energy level, resulting in currents. Electrons in conductors, rather than being free-moving, are typically confined to orbitals within their respective molecules, below the energy level of these conducting tunnels. Raising electrons into the tunnels requires energy, which manifests as electrical resistance. The resistance of a conductor can be reduced by compressing the molecular spacing, which minimizes the gap between the tunnels and valence orbitals. This gap can be further reduced to zero with additional pressure, resulting in the tunnels overlapping with valence orbitals. Consequently, electrons reside naturally within the tunnels without a need for the lifting energy to the tunnels, resulting in zero resistance—superconductivity. This theory comprehensively explains observed superconducting phenomena, including the Meissner effect, critical current density, critical magnetic field, the inverse relationship between resistivity and pressure, and why many high-temperature superconductors are achieved under high pressures. According to this theory, compressing molecular distances is the key to synthesizing room-temperature superconductors. An optimal approach involves engineering molecular structures to leverage attraction between specific molecules, thereby minimizing the gap.