Vol. 8,No. 8,August 1969
NOTES 1775
could w7ell be t h a t the energy difference between the octahedron and the trigonal prism is small in a very large number of cases and t h a t the reason the Bailar twist mechanism is not generally observed is due, not to its unfavorable activation energy, as suggested by some authors,lO,llbut rather to its unusually low frequency factor.
bridges of OMPA and NIPA. Complexes of selected metal ions with PCP have been prepared and will be discussed in this paper. The structure of the ligand is
(lo) I
