Chapter 4: MD Example Flashcards
1
Q
MD Interactions
A
- short-range repulsion: Pauli exclusion principle
- mid-range attraction: dispersion
- long-range: electrostatics
2
Q
Lennard-Jones Potential
A
- one of simplest ways to capture short- and mid-range interactions

3
Q
Lennard-Jones Potential
(Graph)
A
- min{VLJ(r)} = VLJ(21/6) = -ε

4
Q
Lennard-Jones Potential
(Cut-off Distance)
A
- cannot do infinite integral → introduce cut-off distance rc
- typically rc = 2.5σ
- use to shift potential so that VLJ(r>|rc) = 0
5
Q
Simulation Units
A
- reduced (dimensionless) units are useful → no rounding errors
- For mechanical systen, need three independent units
- e.g. mass, energy, length
- addition of electrostatics requires fundamental charge eo
- e.g. mass, energy, length
6
Q
Law of Corresponding States
A
Using reduced units allows simulation of a class of systems, rather than specific example-systems