Hydrogen bonds crystal engineering

Hydrogen-Bonded Ribbons, Tapes and Sheets as Motifs for Crystal Engineering... 

Crystal Engineering Using Multiple Hydrogen Bonds A. D. Burrows... 

Braga D, Maini L, Polito M, Grepioni F (2004) Hydrogen Bonding Interactions Between Ions A Powerful Tool in Molecular Crystal Engineering 111 1-32 Brechin EK, see Aromf G (2006) 122 1-67... 

Burrows AD (2004) Crystal Engineering Using Multiple Hydrogen Bonds 108 55-96 Bussmann-Holder A, Dalai NS (2007) Order/Disorder Versus or with Displacive Dynamics in Ferroelectric Systems. 124 1-21... 

Strong intermolecular interactions between active SCO mononuclear building blocks stem from the presence of efficient hydrogen-bonding networks or 7i-7i stacking interactions and have led to abrupt spin transitions [1], sometimes with associated hysteresis [2-4]. Despite the important efforts made by crystal engineers in establishing reliable connections between molecular and supramolecular structures on the basis of intermolecular interactions, the control of such forces is, however, difficult and becomes even more complicated when uncoordinated counter-ions and/or solvent molecules are present in the crystal lattice. 

Because of the vastness of the subject matter, we shall focus our attention on hydrogen bonding interactions between ions and on the possibilities and limitations of their use in the design and construction of molecular materials of desired architectures and/or destined to predetermined functions. Obviously, the crystal engineer (or supramolecular chemist) needs to know the nature of the forces s/he is planning to master, since molecular and ionic crystals, even if constructed with similar building blocks, differ substantially in chemical and physical properties (solubility, melting points, conductivity, mechanical robustness, etc.). 

Hydrogen Bonding Interactions Between Ions A Powerful Tool in Molecular Crystal Engineering... 

The principal non-covalent interaction in molecule-based crystal engineering is the hydrogen bond. The reason for this preference is simple, the hydrogen bond is the strongest of the non-covalent interactions and possesses a high degree of directionality. Strength and directionality (namely transferability and repro-... 

We have referred to salt formation, design of hydrogen-bond frameworks, and use of charge-transfer interactions as possible techniques for crystal engineering. These techniques are certainly as applicable to two-component as to one-component systems. 

It is obvious that these molecular systems can be prepared specially or can form spontaneously as self-assemblies when hydrogen or dihydrogen bonds dictate the processes of molecular aggregation. The latter is particularly importaut in supramolecular chemistry and crystal engineering, where the primary attention is focused on mastering weak intermolecular interactions [1]. 

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