Stereochemistry of As, Sb, and Bi

The series As, Sb, and Bi show a gradation of properties from non-metallic to metallic, but the discrete molecules and ions of these elements exhibit similar stereochemistry, as listed in Table 15.6.1 and shown in Fig. 15.6.1. The presence of a lone pair (denoted by E in the table) in these atoms implies Mm otherwise it is Mv. 

Structure of phospholyl n complexes (a)-(e) sandwich-type phosphametallocenes, (f) Sn[tj5-PC4(TMS)2Cp2]2, 

Total number of electron pairs General formula Geometry Example (refer to Fig. 15.6.1) 

4 mx3e Trigonal pyramidal AsC13, SbCl3, BiCl3 (a) 

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