The short-time orientational relaxation of water is studied by ultrafast infrared pump-probe spectroscopy of the hydroxyl stretching mode (OD of dilute HOD in H(2)O). The anisotropy decay displays a sharp drop at very short times caused by inertial orientational motion, followed by a much slower decay that fully randomizes the orientation. Investigation of temperatures from 1 degrees C to 65 de...

The effects of ion charge, polarity and size on the surface morphology of size-selected aqueous nanodrops containing a single ion and up to 550 water molecules are investigated with infrared photodissociation (IRPD) spectroscopy and theory. IRPD spectra of M(H2O)n where M 1⁄4 La, Ca, Na, Li, I , SO4 and supporting molecular dynamics simulations indicate that strong interactions between multiply...

Spectroscopic and theoretical investigations have been carried out for neutral phenol-triethylsilane clusters to reveal an intrinsic nature of the Si-H···H-O type dihydrogen bond. On the basis of the laser-induced fluorescence and infrared spectra, four isomers are identified. Three of them have a structure in which the dihydrogen bond and the dispersion interaction are competing in the stabili...

A microscale mathematical model of blood clot dissolution based on coarse-grained molecular dynamics is presented. In the model, a blood clot is assumed to be an assembly of blood cells interconnected with elastic fibrin bonds, which are cleaved either biochemically (bond degradation) or mechanically (bond overstretching) during flow-mediated thrombolysis. The effect of a thrombolytic agent on ...

The relation between spectroscopic observables and the detailed metal–ligand bonding features in chelation complexes is addressed using both experimental and state-of-the-art theoretical and computational methods. We synthesized and characterized a set of six nickel dicarbonyl complexes of general formula [Ni(CO)2(PP)], where PP is an atropoisomeric chelating diphosphine ligand. The analysis of...

An ab-initio computational study was performed to investigate the effect of explicit hydration on the ground and lowest singlet PiPi* excited-state geometry and on the selected stretching vibrational frequencies corresponding to the different NH sites of the guanine acting as hydrogen-bond donors. The studied systems consisted of guanine interacting with one, three, five, six, and seven water m...

The 400-4000 cm(-1) FTIR spectra of pure NH and isotopically substituted (10 and 90% doped ND/NH) polycrystalline L-alanine were recorded in the temperature range 10-300 K. The observed temperature dependence and isotopic shifts behavior enabled to identify, in the spectra of the doped crystals, three well-separated bands ascribable to either the NH or ND stretching vibrations associated with t...

In this study, we have determined the structure of a medicinally important molecule saligenin (2-hydroxybenzyl alcohol) using UV, IR and microwave absorption spectroscopy in a supersonic jet combined with ab initio calculations. The structure of the only observed conformer of saligenin corresponds to the global minimum on the conformational surface. The observed structure is stabilized by an in...