Hydrogen bonded systems, solvation

C. S. Callam, S. J. Singer, T. F. Fowary, and C. M. Hadad, Computational analysis of the potential energy surfaces of glycerol in the gas and aqueous phases Effects of level of theory, basis set, and solvation on strongly intramolecularly hydrogen bonded systems. J. Am. Chem. Soc. 123, 11743 11754 (2001). 

Bopp, P. (1987). Molecular dynamics computer simulations of solvation in hydrogen bonded systems. Pure Appl. Chem. 59, 1071-82. 

Sometimes the problem of solvation may be reduced to the investigation of hydrogen-bonded systems of the type (AH "A) , that represent an important entity in aqueous solutions of electrolytes. These systems possess double-well proton potential curves, if the A-A distance is larger than about 2.4 x 10 m. Such a hydrogen bond is... 

The reverse micelle and the associated structural properties that were investigated in this section, require the detailed level of description to describe phenomena such as ion-exchange or the hydrophobic effect. Thus, water is treated explicitly in these systems to capture effects associated with hydrogen bonding and solvation. In what follows, we will illustrate phenomena in which this level of atomistic detail is not required and the solvent (water) is treated as a bead that represents a group of water molecules and hydrocarbon chains treated as a collection of beads to represent lipid molecules. These reduced descriptions, which form the basis for mesoscale descriptions, are able to probe phenomena on larger length and time scales compared with the fully atomistic descriptions. 

Not only it is difficult to distinguish between a co-crystal and a solvate (as a matter of fact all molecules are solid and form crystals at sufficiently low temperature) but it is also often difficult to distinguish between a crystal and a salt. As discussed above in the case of hydrogen-bonded systems between acids and bases the transition between a salt and a co-crystal may be a very semantic issue depending exclusively on the position of a proton along a N O supramolecular link [90]. 

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