Related Experiment Video
Updated: Jun 12, 2026

Discovery and Synthesis Optimization of Isoreticular Al(III) Phosphonate-Based Metal-Organic Framework Compounds Using High-Throughput Methods
Published on: October 6, 2023
Polymorphs of DABCO monohydrate as structural analogues of NaCl
Barbara Wicher1, Maria Gdaniec
1Faculty of Chemistry, Adam Mickiewicz University, 60-780 Poznań, Poland.
Abstract:
A new crystalline form of 1,4-diazabicyclo[2.2.2]octane (DABCO) monohydrate, C(6)H(12)N(2).H(2)O, crystallizing in the space group P3(1), has been identified during screening for cocrystals. There are three DABCO and three water molecules in the asymmetric unit, with two DABCO molecules exhibiting disorder over two positions related by rotation around the N...N axis. As in the monoclinic C2/c (Z' = 2) polymorph, the molecular components are connected via O-H...N hydrogen bonds into a polymeric structure that consists of linear O-H...N(CH(2)CH(2))(3)N...H-O segments, which are approximately mutually perpendicular. The two polymorphic forms of DABCO monohydrate can be considered as structural analogues of NaCl, with the nearly globular DABCO molecules showing distorted cubic closest packing and all octahedral interstices occupied by water molecules.
Related Concept Videos
Ionic Crystal Structures
Most monatomic ions behave as charged spheres, and their attraction for ions of opposite charge is the same in every direction. Consequently, stable structures for ionic compounds result (1) when ions of one charge are surrounded by as many ions as possible of the opposite...
Ionic Compounds: Formulas and Nomenclature
Structural Isomerism
Isomers are different chemical species that have the same chemical formula. Structural isomerism of coordination compounds can be divided into two subcategories, the linkage isomers and coordination-sphere isomers.
Linkage isomers occur when the coordination compound contains a ligand that can bind to the transition metal center through two different atoms. For example, the CN− ligand can bind through the carbon atom or through the nitrogen atom. Similarly, SCN− can be...
Factors Affecting Dissolution: Polymorphism, Amorphism and Pseudopolymorphism
Some polymorphic crystals possess lower aqueous solubility than their amorphous counterparts, leading to incomplete absorption. For instance, the oral suspension of Chloramphenicol, which...
Hydration of Cement
Coordination Compounds and Nomenclature

