The bare hydrogen ion (a proton) has an extremely high charge density (~2x1010 that of Na+), readily hydrates f and cannot exist freely in solution. Initial hydration forms the hydroxonium ion (H3O+) (commonly called the hydrogen ion and isolelectronic with ammonia, NH3).
It has been shown that H3O+ can donate three hydrogen bonds (but accepts almost none); the strength of these donated hydrogen bonds being over twice as strong as those between H2O molecules in bulk water. A recent study of lone pairs shows the hydronium ion as not possessing the expected lone pair as these electrons are spread out over the three protons and there is no minimum in the electrostatic potential in the expected place. This effectively means that the H3O+ cation can be considered as H9O4+ in solution.
Effects of hydrogen sulfide on mitochondria of lung in rats with ALI induced by lipopolysaccharide
It could be concluded that LPS induce mitochondrial structural damage and functional impairment in rats with ALI induced by LPS, and H2S have a beneficial effect against ALI induced by LPS with decreasing the mitochondrial lipid peroxidation level and protecting the cell structure and function, and the effect is correlated with the dosage.
H-Bond Acceptor Parameters for Anions
The results demonstrate the transferability of H-bond parameters for anions between different solvents and different HBD partners, allowing reliable prediction of anion recognition properties in other scenarios. Carboxylates are the strongest HBAs studied, with β parameters (≈ 15) that are significantly higher than those of neutral organic HBAs, and the non-coordinating anion hexafluorophosphate is the weakest acceptor, with a β parameter comparable to that of pyridine. The effects of ion pairing with the counter-cation were found to be negligible, provided small polar cations were avoided in the less polar solvent (chloroform).
Probing molecular interaction in ionic liquids by low frequency spectroscopy: Coulomb energy, hydrogen bonding and dispersion forces.
The total interaction between cations and anions is a result of a subtle balance between Coulomb forces, hydrogen bonds and dispersion forces. Low frequency spectroscopy can also be used for studying ion speciation. Low vibrational features can be assigned to contact ion pairs and solvent separated ion pairs.
Detailed knowledge of the low frequency spectra can be used to understand the change in interaction strength and structure by variation of temperature, solvent polarity and solvent concentration in ionic liquids and their mixtures with molecular solvents.