Anhydrous tin and lead hexacyanoferrates (II).: Part I. Synthesis and crystal structure.

The crystal structure of Pb₂Fe(CN)₆ and Sn₂Fe(CN)₆ has been first determined and refined using the Rietveld method with combined CuKα₁ X-ray and constant-wavelength neutron powder diffraction data in space group P-3 (147, Z=1). The unit cell constants are a=7.1346(1) and 7.1805(1) Å, c=5.4531(2) and 5.3639(1) Å, respectively. The compounds are layered, groups of three nearest [Fe(CN)₆]⁴⁻-complexes are joined to layers by means of Pb or Sn atoms. The same Pb or Sn atoms (c.n.=3+3) joint three nearest complexes from the next layer. The jointing goes through ‘nitrogenlead(tin)nitrogen’ bonds.