Electron Contribution to Specific Heat One of the great mysteries in physics in the early part of the 20th century was why electrons didn't appear to contribute to specific heat. How could they contribute to electrical conduction and heat conduction and not to specific heat? The electrons in the metal which contribute to conduction are very close to the Fermi level, "ripples on the Fermi sea". But to contribute to bulk specific heat, all the valence electrons would have to receive energy from the nominal thermal energy kT. But The Fermi energy is much greater than kT and the ovewhelming majority of the electrons cannnot receive such energy since there are no available energy levels within kT of their energy. The small fraction of electrons which are within kT of the Fermi level does contribute a small specific heat, and this electron specific heat becomes significant at very low temperatures.

Index Reference Rohlf Ch 14.

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Electron Specific Heat Using Fermi-Dirac statistics (as opposed to Einstein-Bose for phonons), a small fraction of the electrons are available to participate in specific heat. This fraction contributes a specific heat: It is important only for low temperatures in metals where it becomes larger than the T-cubed dependent phonon contribution. At those low temperatures is becomes part of the Einstein-Debye specific heat expression. Discussion of electron role in specific heat

Index Reference Rohlf Ch 14.

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