Thermodynamics and Statistical Mechanics

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Thermodynamics and Statistical Mechanics

• Heat Capacities

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Diatomic Gas

• A gas of diatomic molecules can have
  translational, rotational and vibrational energy.
  Because of the spacing of the energy levels of
  each type of motion, they are not all equally
  excited. This shows up in the heat capacity.

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Partition Function
For one molecule, e etrans erot evib
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Partition Function
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Translational Motion
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Vibrational Motion
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High and Low Temperature Limits
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Rotational Motion
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Rotational Motion
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Diatomic Gas Overall
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Graph
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Einstein Solid
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Einstein Temperature
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Einstein Heat Capacity
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Debye Model of Solid

• The solid is treated as a continuum, calculating
  the number of standing wave states in the
  frequency range between w and w d w, and
  Bose-Einstein statistics is used to determine the
  number of phonons in each state. Then the energy
  can be calculated.

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Density of States (Lec 17)
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Transverse and Longitudinal
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Density of States
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Phonon Energy
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Debye Cutoff
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Debye Temperature
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Energy
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Heat Capacity
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Debye Heat Capacity
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High Temperature
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Low Temperature