Liquid chromatography (LC) may be simply described as an analytical technique used to separate the individual components of a solution based on their relative afRnities for a liquid mobile phase and a stationary phase. There are numerous modes of LC (i.e. reversed-phase, normal-phase, ion exchange) that are commonly classiRed according to the mechanism by which separation occurs. One such mecha...

The presence of specific hydrocarbon gas molecules in various types of water cavities in natural gas hydrates (NGHs) are governed by the relative stabilities of these encapsulated guest molecule-water cavity combinations. Using molecular quantum chemical dispersion-corrected hybrid density functional computations, the interaction (ΔE(host--guest)) and cohesive energies (ΔE(coh)), enthalpies, an...

We present a redox-responsive self-assembly based on a unimolecular platform. Three double-headed amphiphilic molecules composed of β-cyclodextrin (β-CD) and ferrocene (Fc) each with an alkyl chain as a linker (βCD-Cm-Fc, m = 2, 6, and 10) were synthesized, and their self-assembly behaviors were investigated. The molecules self-assembled into polydisperse micelles that transformed into vesicles...

Supramolecular host-guest systems play an important role for a wide range of applications in chemistry and biology. The prediction of the stability of host-guest complexes represents a great challenge to first-principles calculations due to an interplay of a wide variety of covalent and noncovalent interactions in these systems. In particular, van der Waals (vdW) dispersion interactions frequen...

Encapsulation complexes are assemblies in which a reversibly formed host more or less completely surrounds guest molecules. Host structures held together by hydrogen bonds have lifetimes in organic solvents of milliseconds to hours, long enough to directly observe the encapsulated guest by NMR spectroscopy. We describe here the action of alkyl ammonium compounds as guests that gather up to six ...

The relaxation times r of the slowest processes in the parallel dielectric permittivity of various nematic guest-host systems have been measured as a function of temperature. A correlation between r and its temperature dependence is found, indicating increasing temperature dependence for increasing T, independent of structural details of the guest molecules or properties of the host matrices wh...

In a systematic study of molecular recognition of amino acid derivatives in solid-state β-cyclodextrin (β-CD) complexes, we have determined crystal structures for complexes of β-cyclodextrin/N-acetyl-L-phenylalanine at 298 and 20 K and for N-acetyl-D-phenylalanine at 298 K. The crystal structures for the N-acetyl-L-phenylalanine complex present disordered inclusion complexes for which the distr...

Tetraarylpyrenes H1-H4 that typify molecular systems with orthogonal planes and lack hydrogen bonding functional groups were designed as new host systems with three distinct domains for guest inclusion. In particular, H2 and H4 hosts are found to include a variety of guest molecules. We have determined 42 crystal structures overall (i) to establish the importance of skeletal features of the hos...

The dynamic behaviours of host frameworks and guest molecules have received much attention for their great relevance with smart materials, but little has been developed to control or understand the host-guest interplay. Here we show that the confined guest can utilize not only molecular static effects but also bulk dynamic properties to control the host dynamics. By virtue of the three-dimensio...

This work presents a systematic study on the host-guest interactions between the macrocyclic host molecule cucurbit[7]uril (CB[7]) and amino acids (AAs) including three basic AAs (Lys, Arg, and His) and three aromatic AAs (Phe, Tyr, and Trp) to elucidate the origin of the high selectivity of CB[7] toward AA residues in proteins. Complex formation between CB[7] and each AA was examined in soluti...