Chapter 6: Radial Distribution Function Flashcards Preview

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Flashcards in Chapter 6: Radial Distribution Function Deck (5):
1

Radial Distribution Function

Describes probability of finding a pair of particles separated by a distance r relative to probabilty for a completely random distribution with same density 

  • g() = 1 for ideal gas
  • g() can be measured experimentally from scattering experiments
  • many static observables in equilibrium can be measured via g() (e.g. Kirkwood-Buff Theory) 

2

Diffusion Constant 
(Einstein Method)

3

Diffusion Constant 
(Einstein Method: Protocol)

  1. Calculate MSD
  2. Fit function

4

Diffusion Constant 
(Graph)

  • ballistic regime: (α = 2) time-period before interactions become likely
  • diffusive regime: (α = 1)
  • Special Cases
    • α > 1 : super diffusion
    • α 

5

Green-Kubo Relations

relates transport properties to auto integrals over autocorrelation functions

  • e.g. diffusion (see below)