Cover illustration: View of the porous framework of poly[[(2-4,4'-bipyridine)(3-5-isonicotinamidoisophthalato)cobalt(II)] trihydrate] along the b axis. See Deng, Xu, Chen & Zhang [Acta Cryst. (2012), C68, m219-m222].
The two investigated compounds have similar [CoBP2O8]− anionic frameworks but differ in their (K,Ca)/H2O disorder schemes. In the structure of the pure potassium borophosphate, the solvent water molecules and a fraction of the alkali cations are located within the helical channels.
Orthorhombic ternary La2LiGe6+x (x = 0.21) (space group Cmmm, Pr2LiGe6 type) and La2LiGe44Si2, which crystallizes as an ordered variant of this type, are new representatives of a homologous linear series based on structural fragments of the AlB2, CaF2 and ZrSi2 structure types.