Structure
The crystal structure of solid lead(II) nitrate has been determined by neutron diffraction. The compound crystallises in the cubic system with the lead atoms in a face-centred cubic system. Its space group is Pa3Z=4 (Bravais lattice notation), with each side of the cube with length 784 picometres.
The black dots represent the lead atoms, the white dots the nitrate groups 27 picometres above the plane of the lead atoms, and the blue dots the nitrate groups the same distance below this plane. In this configuration, every lead atom is bonded to twelve oxygen atoms (bond length: 281 pm). All N–O bond lengths are identical, at 127 picometres.
Research interest in the crystal structure of lead(II) nitrate was partly based on the possibility of free internal rotation of the nitrate groups within the crystal lattice at elevated temperatures, but this did not materialise.
Read more about this topic: Lead(II) Nitrate
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