Coordination geometries of phosphorus

Phosphorus forms various compounds with all elements except Sb, Bi, and the inert gases for the binary compounds. The stereochemistry and bonding of phosphorus are very varied. Some typical coordination geometries are summarized in Table 15.4.1 and illustrated in Fig. 15.4.2. Many of these compounds will be discussed below. 

Coordination number 1 is represented by the compounds PsN, PeeC-H, PeeC-X (X = F, Cl), and P=C-Ar (Ar = Bu3CV,H2). In these compounds, the P atom 

Compounds of this coordination number have three bond types  

In compounds of this coordination number, the pyramidal configuration is the most common type, and the planar one is much less favored. In pyramidal PX3, the three X groups are either the same or different, X = F, Cl, Br, I, H, OR, OPh, Ph, Bu, etc. The observed data of some PX3 compounds are listed below  

Since PX3 has a lone pair at the P atom and the X groups can be varied, the molecules PX3 are important ligands. The strength of the coordinate bond X3P— -M is influenced by different X groups in three aspects  

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Table 15.4.1. Coordination geometries of phosphorus atoms in compounds...

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