DistanceBetweenCentersOfMass

The DistanceBetweenCentersOfMass step calculates and records the distances between the centers of mass of specified groups of particles.

Output format:

# step distance_group_pair_1 distance_group_pair_2 distance_group_pair_3 ...
0 5.678 10.123 15.456
100 5.789 10.234 15.567
200 5.890 10.345 15.678

---

• type: GeometricalMeasure, DistanceBetweenCentersOfMass

• parameters:

  • outputFilePath: string: Path to the output file

• data:

  • name: string: Name of the group

  • id_list: int[]: List of particle IDs in the group

Example:

"comDistances":{
  "type":["GeometricalMeasure","DistanceBetweenCentersOfMass"],
  "parameters":{
    "intervalStep": 10000,
    "outputFilePath": "com_distances.dat"
  },
  "labels":["idSet_i","idSet_j"],
  "data":[
    [[1, 2, 3, 4, 5],[6, 7, 8, 9, 10]],
    [[11, 12, 13, 14, 15],[16, 17, 18, 19, 20]],
    [[21, 22, 23, 24, 25],[26, 27, 28, 29, 30]]
  ]
}

Note

The output file will contain the step number and the distances between all pairs of specified groups.

Tip

This measure is useful for tracking the relative motion of different parts of the system, such as in protein-ligand interactions or polymer aggregation studies.