Polyhedral Skeletal Electron Pair Theory The Wade-Mingos Rules

Polyhedral Skeletal Electron Pair Theory The Wade-Mingos Rules 

2n + 4 electrons 5 vertices square pyramid B5H9 nido  

The next important contribution in this area was made shortly thereafter by Wade [16], who recognized that this structural relationship could be related to the number of valence electrons associated with skeletal bonding in the boranes. Thus deprotonation of all of the bridging hydrogens from the related series of boranes B H 2T B iH(n 1)+4, and Bn 2H( 2)+6 gives the ions B H 2 , B H,- 4-, and B -2H 26-. All of these ions can readily be seen to have the same number of skeletal electron pairs, namely it +1, corresponding to 2it + 2 skeletal electrons. 

Balakrishnarajan and Jemmis [32, 33] have very recently extended the Wade-Mingos rules from isolated borane deltahedra to fused borane ( conjuncto ) delta -hedra. They arrive at the requirement of n I m skeletal electron pairs corresponding to 2n + 2m skeletal electrons for such fused deltahedra having n total vertices and m individual deltahedra. Note that for a single deltahedron (i.e., m = 1) the Jemmis 2n + 2m rule reduces to the Wade-Mingos 2n I 2 rule. 

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B. Deltahedral Boranes and Polyhedral Skeletal Electron Pair Theory The Wade-Mingos Rules... 

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