Two properties render electrolyte theories difficult, namely the long-range nature of the Coulomb interactions and the high figures of the Coulomb energy at small ion separations. In solvents of low dielectric constant, where the Coulomb interactions are particularly strong, electrical conductance and dielectric spectra suggest that the ion distribution involves dipolar ion pairs, which then in...

Although the radical ion pair has been frequently invoked as a key intermediate in DNA oxidative damage reactions and photoinduced electron transfer processes, the unambiguous detection and characterization of this species remain formidable and unresolved due to its extremely unstable nature and low concentration. We use the strategy that, at cryogenic temperatures, the transient species could ...

In multiphase extraction [18F]fluoride ion for radiolabeling is recovered from target water by passage through a small column of microporous polymer impregnated with a lipophilic cryptand or quaternary ammonium salt. The 18O enriched water can be recovered for reuse. The [18F]fluoride ion-pair is eluted from the column by a small volume of acetonitrile or other organic solvent. Evaporation of t...

The existence of like-charge guanidinium-guanidinium contact ion pairs in water is established by ab initio molecular dynamics simulations. Despite direct electrostatic repulsion a contact ion pair is observed between two guanidinium cations, stabilized primarily by their amphiphilic behavior and van der Waals interactions. In a control simulation performed for two aqueous ammonium cations no s...

A high-performance liquid chromatographic method using fluorescence detection for the simultaneous determination of furosemide and amiloride is described. The chromatographic system is based on reversed-phase ion-pair chromatography with sodium dodecylsulphate as ion-pairing agent. The same counter-ion is used for the ion-pair liquid-liquid extraction to ethyl acetate. The minimum detectable co...

MP2/aug'-cc-pVTZ calculations have been carried out to investigate the halogen-bonded complexes formed when CO and CS act as electron-pair donors through C to ClF, ClNC, ClCl, ClOH, ClCN, ClCCH, and ClNH₂. CO forms only complexes stabilized by traditional halogen bonds, and all ClY molecules form traditional halogen-bonded complexes with SC, except ClF which forms only an ion-pair complex. Ion-...

An unprecedented family of novel electron-donor acceptor conjugates based on fullerenes as electron acceptors, on one hand, and triphenyl amines as electron donors, on the other hand, have been synthesized and characterized in a variety of solvents using steady state absorption/emission as well as transient absorption spectroscopy. These are unprecedented in terms of their outcome of radical io...

The spin dynamics of radical pairs from ion-pair complexes between viologen and tetraarylborate compounds have been investigated in the presence microwave (μw) radiation, using steady-state electron paramagnetic resonance to follow pair dynamics.