Identification of a Near‐Linear Supramolecular Water Dimer, (H₂O)₂, in the Channel of an Inorganic Framework Material.

Abstract

6n [Al(OH) 6 Mo 6 O 18 ] n ·2nH 2 O are prepared by reaction of Na 2 MoO 4 with an acidified aqueous solution of AlCl 3 (pH 1.8, 20-22°C, 7 d, 68% yield). The samples are characterized by vibrational spectroscopy, powder and single XRD, and TG-DSC analyses. The compound crystallizes in the triclinic space group P1 with Z = 3. It has a three-dimensional framework structure with well-defined "S"-shaped channels. These channels encapsulate supramolecular water dimers as guests furnishing a novel example of a near-linear (H 2 O) 2 cluster in the solid state. -(MANIKUMARI, S.; SHIVAIAH, V.; DAS*, S. K.; Inorg.

3-Picoline Mediated Self-Assembly of M(II)–Malonate Complexes (M = Ni/Co/Mn/Mg/Zn/Cu) Assisted by Various Weak Forces Involving Lone Pair−π, π–π, and Anion···π–Hole Interactions

“…In our case, a discrete water dimer has been identified in the crystal lattice of complexes 1 – 5 and it plays an important role by stitching aforementioned 1D tapes to generate a 2D network along b axis (Figure ). Such small water clusters, [(H 2 O) n , n = 2–10], have attracted much attention from both theoretical and experimental aspects, because they help in understanding structure and characteristics of bulk water or ice and are well documented in the literature. − In this context, the work of Saykally and co-workers is worth mentioning . In our case, Two water molecules form a near linear supramolecular water dimer with average O --- O distance being 2.8476 Å in complexes 1 – 5 .…”

“…In our case, Two water molecules form a near linear supramolecular water dimer with average O --- O distance being 2.8476 Å in complexes 1 – 5 . For comparison, the corresponding values in regular ice, in liquid water, and in the vapor phase are 2.74, 2.85, and 2.98 Å, respectively. − Overall 3D packing (Figure ) is achieved by various hydrogen bonds in 1 – 5 .…”