The influence of temperature on the proton location in hydrogen bonds has been systematically studied by neutron diffraction in only a few crystal structures. Two of these are the 1:1 complex of urea - phosphoric acid with an OHO hydrogen bond and 4-methylpyridine -pentachlorophenol with an OHN hydrogen bond. Based on these earlier determined crystal structures the potential energy surface (PES...

The amino alcohol meglumine solubilizes organic compounds in water and enforces the formation of electron donor acceptor (EDA) complexes haloarenes with indoles, anilines, anisoles or thiols, which are not observed solvents. UV-A photoinduced transfer within EDA induces mesolytic cleavage halide ion radical recombination arenes leading, after rearomatization proton loss to C?C C?S coupling prod...

A ruthenium(II) complex with two 4,4'-bis(trifluoromethyl)-2,2'-bipyridine chelates and a 2-(2'-pyridyl)imidazole ligand was synthesized and characterized by electrochemical and optical spectroscopic means. The respective complex has the potential to act as a combined electron-proton donor when promoted to its long-lived (3)MLCT excited state with visible light. The possibility of proton-couple...

The proton transfer activity of the light-driven proton pump, bacteriorhodopsin (bR) in the photochemical cycle might imply internal water molecules. The free energy of inserting water molecules in specific sites along the bR transmembrane channel has been calculated using molecular dynamics simulations based on a microscopic model. The existence of internal hydration is related to the free ene...

In the present work, the joint use of the potential energy, the reaction electronic flux profiles and NBO analysis along the intrinsic reaction coordinate within the framework of the reaction force analysis allows us to gain insights into the mechanism of the proton transfer process in amino acids. The reaction was studied in alanine and phenylalanine in the presence of a continuum and with add...

GTPases play a crucial role in the regulation of many biological processes by catalyzing the hydrolysis of GTP into GDP. The focus of this work is on the dynamin-related large GTPase human guanine nucleotide binding protein-1 (hGBP1) which is able to hydrolyze GTP even to GMP. Here, we studied the largely unknown mechanisms of both GTP and GDP hydrolysis steps utilizing accelerated ab initio QM...

GTPases play a crucial role in the regulation of many biological processes by catalyzing the hydrolysis of GTP into GDP. The focus of this work is on the dynamin-related large GTPase human guanine nucleotide binding protein-1 (hGBP1) which is able to hydrolyze GTP even to GMP. Here, we studied the largely unknown mechanisms of both GTP and GDP hydrolysis steps utilizing accelerated ab initio QM...

Near-neutral aqueous electrolytes are to be preferred for the development of sustainable electrochemical energy conversion and storage devices. Protons inherent these their reactivity toward electrode material extends beyond own reduction, especially when reversible proton insertion takes place in bulk from acidic or buffered electrolytes. However, a still burning question is regarding whether ...

The complexes between trans-N-methylformamide (t-NMF) and Ar, N(2), CO, H(2)O have been studied by infrared matrix isolation spectroscopy and/or ab initio calculations. The infrared spectra of NMF/Ne, NMF/Ar and NMF/N(2)(CO,H(2)O)/Ar matrices have been measured and the effect of the complexation on the perturbation of t-NMF frequencies was analyzed. The geometries of the complexes formed betwee...

The biological functions of many proteins are crucially coupled to protonation equilibria, for instance, in the enzymatic reactions of serine proteases and carbonic anhydrase, and in integral membrane proton pumps such as bacteriorhodopsin, cytochrome c oxidase (COX), and FOF1-ATP synthase. [8] Proton-transfer (PT) reactions are also crucial in many other areas of chemistry, such as membrane pe...