2: Lattice Model of a Fluid
- Page ID
- 294275
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- 2.1: Lattice Models
- Lattice models provide a minimalist, or coarse-grained, framework for describing the translational, rotational, and conformational degrees of freedom of molecules, and are particularly useful for problems in which entropy of mixing, configurational entropy, or excluded volume are key variables. The lattice forms a basis for enumerating different configurations of the system, or microstates. Each microstates may have a different energy, which is then used to calculate partition functions.
- 2.2: Ideal Lattice Gas
- The description of a weakly interacting fluid, gas, solution, or mixture is dominated by the translational entropy or entropy of mixing. In this case, we are dealing with how molecules occupy a volume, which leads to a translational partition function.