Chapter 15: Simulation of Soft-Matter Systems Flashcards
1
Q
Examples of Soft-Matter
A
proteins, membranes, polymers, colloids, liquid crystals
2
Q
Polymer Model Goals
A
measure diffusion or other thermodynamic observables in corase-grained models
3
Q
End-to-End Distance and Radius of Gyration
A
-
End-to-End Distance:
- gives information about spatial extension of polymer
-
Radius of Gyration:
- gives information about density (i.e. how curled-up is the polymer)
4
Q
Ideal Chain Polymer
A
- no long-range interaction (i.e. freely jointed chain)
- random walk model
- nearest-neighbor interactions only
5
Q
Types of Solvent
A
statistics of polymer depend on the solubility of polymer in solvent
- Θ-Solvent
- Good Solvent
- Poor Solvent
- FENE Model
6
Q
Θ-Solvent
A
- implicit solvent
- ideal chain model
- harmonic potential
7
Q
Good Solvent
A
- monomers have size → excluded volume interactions
- from WCA potential
8
Q
Poor Solvent
A
- LJ interaction
9
Q
FENE Model
A
- finitely extensible non-linear elastic model
- uses non-linear springs
10
Q
Flory Exponent
A
characterizes the scaling of radius of gyration
11
Q
Flory Exponent for Solvent Types
A
12
Q
Lattice Models
A
model polymers on a lattice
13
Q
Polyelectrolyte
A
charged polymer with fractional charges
- include Coulomb interactions
- can write in terms of Bjerrum length
14
Q
Bjerrum Length
A
separation distance needed such that VCoul = kT
15
Q
Polyelectrolyte T=0 Groundstate and Flory Exponent
A
- chain
- ν = 1
16
Q
Blob Theory
A
- coarse-graining of polymers into megapolymer blobs
- inside blob, physics is that of neutral polymer
- at large length, polymer behaves like blob
- ν = 1
