The idea of this calculation is to look for path between 2 atoms A and B, respecting the following rules:
Total coordination for A (\(\alpha\)) must be \(\ne\) 2
Total coordination for B (\(\beta\)) must be \(\ne\) 2
Total coordination for all atom(s) between A and B must be equal to 2.
Chains are then litteraly succession of atoms isolated from the rest of the material.
Atomes offers several options to enforce specific definition of a chain for the search:
Total coordination for A and B can be restricted to 1: searching for chains would mean searching for isolated 1 dimensional (on a coordination point of view) structures in the material.
The chemistry of the atoms in the chain(s) can be considered:
Only searching for AAAA (\(\alpha\alpha\alpha\alpha\)) chains (homopolar bonds exclusively).
Excluding homopolar bonds from the search (heteropolar bonds exclusively).
Only searching for ABAB (\(\alpha\beta\alpha\beta\)) chains (perfect alternate of heteropolar bonds.