Distance Geometry Algorithm
- Obtain a conformation with desired bond lengths & angles
- Create and initialize a distance bounds matrix (DBM)
- Set all minimum distances in DBM from VDW radii
- Set all 1-2 and 1-3 distances in DBM from the conformation
- Set all 1-4 distances in DBM for known torsion constraints
- Record planar (0) and chiral (signed) volume constraints
- Smooth DBM using triangle [and tetrangle] inequality
- Select in-range distances randomly or by partial metrization
- Transform DBM to metric matrix (MM)
- Embed MM in 4-space (if unable, go to 8)
- Minimize bounds violations in 4-space (else, go to 8)
- Minimize 4th dimension violations leaving 3-D conformation
- Evaluate distance and volume bounds violations
- Add resulting conformation and errors to output
- If more conformations are need, repeat from 8
Strength and Weaknesses
- The strength of distance geometry is its rapid and effective sampling of conformation space.
- It's weakness is that the conformations are not high quality with respect to energy or chemical common sense.