The intermolecular forces between water molecules are of great importance in many areas of chemistry including solvation, solution chemistry, and biochemistry. As a result of this (H2O)n systems have received a great significant of attention, both experimental and theoretical. All calculation of this study are carried out by Gaussian 98 soft ware. Geometry optimization for each cluster were be ...

q-mode hierarchical cluster (hca) and principal component analysis (pca) were simultaneously applied to groundwater hydrochemical data from the three times in 2004: june, september, and december, along the ain azel aquifer, algeria, to extract principal factors corresponding to the different sources of variation in the hydrochemistry, with the objective of defining the main controls on the h...

One of the fundamental biological reactions, the catalytically activated water-splitting, takes place at an inorganic tetra-manganese monocalcium penta-oxygen (Mn4CaO5) cluster which together with its protein ligands forms the oxygen evolution complex (OEC) of the membrane-bound pigment− protein photosystem II (PSII) of plants, algae, and cyanobacteria. In the first step of a new hierarchical a...

We have succeeded in producing liquid clusters such as ethanol and water clusters by an adiabatic expansion phenomenon, and the cluster size distribution was analyzed by using the time-of-flight method. For ethanol cluster ions, the size was distributed between a few hundreds and a few thousands, and the peak size was approximately 1200 molecules per cluster. For water cluster ions, the size di...

By the Wolff’s cluster Monte Carlo simulations and numerical minimization within a mean field approach, we study the low temperature phase diagram of water, adopting a cell model that reproduces the known properties of water in its fluid phases. Both methods allows us to study the water thermodynamic behavior at temperatures where other numerical approaches –both Monte Carlo and molecular dynam...

Temperature and size effects on the behavior of nanoscale water molecule clusters are investigated by molecular dynamics simulations. The flexible three-centered (F3C) water potential is used to model the inter- and intramolecular interactions of the water molecule. The differences between the structural properties for the surface region and those for the interior region of the cluster are also...

The title tetra-cyanido-nickelate-copper complex, [Cu₂Ni₂(CN)₈(C₁₅H₃₃N₃)₂]·4H₂O, was synthesized by self-assembly using potassium tetracyanidonickelate(II) and dichlorido(1,4,7-triisopropyl-1,4,7-triazacyclononane)copper(II). The asymmetric unit contains half of a complex mol-ecule and two water mol-ecules. The entire complex has -1 symmetry and contains Ni(II) in a slightly distorted square-pl...

In plants, algae and cyanobacteria, Photosystem II (PSII) catalyzes the light-driven splitting of water at a protein-bound Mn4CaO5-cluster, the water-oxidizing complex (WOC). In the photosynthetic organisms, the light-driven formation of the WOC from dissolved metal ions is a key process because it is essential in both initial activation and continuous repair of PSII. Structural information is ...

The analysis of changes in water quality in a monitoring network system is important because the sources of pollution vary in time and space. This study utilized analysis of the water quality index calculation, hierarchical cluster analysis, and mapping. This was achieved by assessing the water quality parameters of the samples collected from Galma River in Zaria, Northwestern Nigeria in wet an...