The electronic geometry of Bi(III) (bismuth in the +3 oxidation state) can be described as trigonal pyramidal. This geometry arises because Bi(III) typically forms three bonds with surrounding atoms and has a lone pair of electrons.
In terms of the VSEPR (Valence Shell Electron Pair Repulsion) theory, the presence of three bonding pairs and one lone pair of electrons around the central bismuth atom leads to this trigonal pyramidal shape. The three bonding pairs occupy the equatorial positions, while the lone pair is positioned at the apex, creating an asymmetrical arrangement. This electronic arrangement results in distinct angles between the bonded atoms, generally around 107 degrees, which is slightly less than the ideal tetrahedral angle due to the repulsion exerted by the lone pair.
To summarize, the electronic geometry of Bi(III) is trigonal pyramidal, reflecting the influence of lone pairs and bonding pairs in determining the spatial arrangement of atoms in the molecule.