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21.4: The Debye Function is Used to Calculate the Heat Capacity at Low Temperatures

  • Page ID
    14481
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    The Debye function has been experimentally determined to calculate the heat capacity at low temperatures, between 0 K and 15 K, for nonmetallic crystals:

    \[\bar{C}_P=aT^3 \nonumber \]

    Constant \(a\) can be found by ensuring \({\bar{C}}_P\) is continuous up to lowest \({\bar{C}}_P\) data point. The Debye function is named after the Dutch chemistry Peter Debye, who theoretically showed this relationship. Metallic crystals have a slightly different equation at low temperature:

    \[\bar{C}_P=aT+bT^3 \nonumber \]

    where \(a\) and \(b\) are constants.


    21.4: The Debye Function is Used to Calculate the Heat Capacity at Low Temperatures is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by LibreTexts.