J. Brocas, THE DSD MODEL IN HEPTACOORDINATE STEREOCHEMISTRY - A COMPARISON WITH EXPERIMENT, Journal of mathematical chemistry, 14(2), 1993, pp. 153-174
The diamond-square-diamond or dsd model provides a simple description
for heptacoordinate interconversion. We compare it to NMR information.
It appears that the model is almost always compatible with experiment
al facts, at least when the dsd processes do not lead to isomerization
.