Among all the chemical substances available in the universe, water, with its deceptively simple formula H₂O, is the most discussed subject either in science or in philosophy [1]. If you are not convinced by this affirmation, a little experiment at no cost may help you change your mind. Just open your favorite web browser and type the word “water” in any search engine. When I have done that using Google, the number of hits was about 682,000,000 (please do not try to read all the pages). In fact, the only words that seem to beat water at this little game are “air” (770,000,000 hits with Google and 3,120,000,000 with Yahoo), and “food” (689,000,000 hits with Google and 3,820,000,000 with Yahoo). Of course this should not be a surprise, as breathing, eating, drinking just mean that you are a living entity. In fact extending the water search to “eau” (French), “wasser” (German), “agua” (Spanish, Portuguese) and “acqua” (Italian) leads to 978,900,000 hits under Google and 3,426,000,000 hits under Yahoo, showing now that water is about as important as food. After all, as everybody knows, “water is life”, and do we really have to read about one billion documents to know at least what water really is? [...] Full article

Thermodynamic and transport properties of liquid water are not fully understood despite a large amount of research work both experimental and theoretical. The maximum of density and the enhanced anomalies observed at low temperatures are at the origin of several models that, in some cases, predict specific and unique behavior such as spinodal lines or critical points. We show that a careful analysis of the neutron quasi-elastic scattering data, both the incoherent spectra and the dynamic of the partials, is compatible with a polymer-like model, where the hydrogen bond dynamics explains the behavior of water in the non-accessible temperature region extending from −30° C to the glass transition. Full article

Liquid water has been recognized long ago to be the matrix of many processes, including life and also rock dynamics. Interactions among biomolecules occur very differently in a non-aqueous system and are unable to produce life. This ability to make living processes possible implies a very peculiar structure of liquid water. According to modern Quantum Field Theory (QFT), a complementary principle (in the sense of Niels Bohr) holds between the number N of field quanta (including the matter field whose quanta are just the atoms/molecules) and the phase Ф. This means that when we focus on the atomic structure of matter it loses its coherence properties and, vice versa, when we examine the phase dynamics of the system its atomic structure becomes undefined. Superfluid liquid Helium is the first example of this peculiar quantum dynamics. In the present paper we show how consideration of the phase dynamics of liquid water makes the understanding of its peculiar role in the onset of self-organization in living organisms and in ecosystems possible. Full article

The radiolysis of water due to ionizing radiation results in the production of electrons, H^· atoms, ^·OH radicals, H₃O⁺ ions and molecules (dihydrogen H₂ and hydrogen peroxide H₂O₂). A brief history of the development of the understanding of water radiolysis is presented, with a focus on the H₂ production. This H₂ production is strongly modified at oxide surfaces. Different parameters accounting for this behavior are presented. Full article

In 1893 Sir William Armstrong placed a cotton thread between two wine glasses filled with chemically pure water. After applying a high voltage, a watery connection formed, and after some time, the cotton thread was pulled into one of the glasses, leaving a rope of water suspended between the two glasses. Although being a very simple experiment, it is of special interest since it comprises a number of phenomena currently tackled in modern water science like electrolysis-less charge transport and nanobubbles. This work gives some background information about water research in general and describes the water bridge phenomenon from the viewpoint of different fields such as electrohydrodynamics and quantum field theory. It is shown that the investigation of the floating water bridge led to new discoveries about water, both in the macroscopic and microscopic realm – but these were merely “hidden” in that sense that they only become evident upon application of electric fields. Full article

A review. Diffraction methods are a powerful tool to investigate the crystal structure of organic compounds in general and their hydrates in particular. The laboratory standard technique of single crystal X-ray diffraction gives information about the molecular conformation, packing and hydrogen bonding in the crystal structure, while powder X-ray diffraction on bulk material can trace hydration/dehydration processes and phase transitions under non-ambient conditions. Neutron diffraction is a valuable complementary technique to X-ray diffraction and gives highly accurate hydrogen atom positions due to the interaction of the radiation with the atomic nuclei. Although not yet often applied to organic hydrates, neutron single crystal and neutron powder diffraction give precise structural data on hydrogen bonding networks which will help explain why hydrates form in the first place. Full article