Cover illustration: The hydrogen-bonded sheet formed by amino-carboxylate interactions between peptide molecules in L-prolyl-L-serine monohydrate. Side-chain atoms have been omitted. Two head-to-tail C(8) chains have been highlighted vertically and single dashed lines indicate N-HO hydrogen bonds between peptide molecules. Double dashed lines show the hydrogen bonding between water molecules producing the water wire. See Görbitz & Yadav [Acta Cryst. (2013), C69, 556-559].
Rb2Cd5As4 and Rb2Zn5Sb4 are new ternary pnictides with a complex orthorhombic structure. In the absence of homoatomic interactions, the chemical bonding can be understood as (Rb+)2(Cd2+)5(As3−)4 and (Rb+)2(Zn2+)5(Sb3−)4, respectively, following the Zintl concept.
The crystal structure of a new oxyfluorotellurate(IV) compound, InTe2O5F, consists of a three-dimensional framework formed by InO4F2 octahedra linked through the F atoms, giving rise to helical chains interconnected via Te2O5 units.