The crystal structure of LaKFe(CN)₆.4H₂O

Abstract

The crystal structure of LaKFe(CN)6.4H20 has been determined from single-crystal X-ray diffraction data and refined by the least-squares method to give R = 2.96 and R w = 3.32%. The space group is P63/m , with a = 7.412 (2) and c = 13.943 (2) ,~. Cyanide bridges link octahedral FeC 6 groups to nine-coordinated LaN6(O3) groups. K ions occupy holes in the structure along the threefold axis. Important bond lengths are: Fe-C = 1.896 (9); La-N = 2.599 (10); La-O = 2.730 (9);C-N = 1.154 (10) A.

Local Structure in Americium and Californium Hexacyanoferrates – Comparison with Their Lanthanide Analogues

“…This evolution is a consequence of the actinide and lanthanide contraction upon going to the higher atomic numbers. Conversely, the situation is very different for the distances within the {Fe(CN) 6 [7][8][9][10][11][12][13][14][15][16][17] …”

“…Values of the Debye-Waller factors are comparable for the first shell but differ significantly for further shells (the coordination numbers being fixed by the model used), as these materials are expected to be significantly disordered (radiation from the actinide-specific activity might be an additional origin of increased disorder as mentioned above). [7][8][9][10][11][12][13][14][15][16][17] ). In all of these structures, the distances within the iron octahedron are on the average d(FeC) = 1.91 Ϯ 0.02 Å and d(CN) = 1.15 Ϯ 0.01 Å.…”

“…The first one, with Ln = La to Nd, presents the general formula KLnFe II (CN) 6 ·4H 2 O. [7,[8][9][10][11] These compounds crystallize in the hexagonal P6 3 /m space group. The second series has a unique representative, KSmFe II (CN) 6 · 3H 2 O, which crystallizes in a monoclinic group (P2 1 /m).…”

Bismuth hexacyanoferrate-modified carbon ceramic electrodes prepared by electrochemical deposition and its electrocatalytic activity towards oxidation of hydrazine

“…3B) and is also consistent with the cyclic voltammetric results of the sample. In XRD spectrum, the major peaks appear at 15.34, 19.02, 24.02, 24.28 and 34.47 are quite similar to that of lanthanide hexacyanoferrate, especially LaHCF [33] due to approximate the same ionic radius between the Bi 3+ ion and the La 3+ ion.…”

On the Lanthanide Ferrocyanides KLnFe(II)(CN)6·xH2O (Ln=La–Lu): Characterization and Thermal Evolution

“…With the larger rare earth elements (Ln=La-Nd), these salts crystallize in the hexagonal P6 3 /m space group (2)(3)(4)(5) which is a substitution derivative of the hexagonal LaFe(CN) 6 Á 5H 2 O (6) in which half of the uncoordinated water molecules are statistically replaced by potassium ions. The next basis member of the series KSmFe(CN) 6 Á 3H 2 O crystallizes in the monoclinic P2 1 /m space group (7), whereas the ferrocyanide hydrate KYbFe(CN) 6 contains only 3.5 H 2 O [half of one of the three coordinated water molecules is missing and the slightly rearranged structure is now orthorhombic, Cmcm space group (8)].…”