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The performance of a selection of theoretical procedures in describing the binding of Ca(super 2+) to ammonia and formaldehyde was assessed. Ca(super 2+) was predicted to bind more strongly to formaldehyde than to ammonia, in contrast to the ordering of proton and Li(super +1) affinities for the two molecules.

Interaction between the surface of the calcium pyrophosphate dihydrate (CPPD) crystals and the extracellular layer of the hydrated dimyristoyl phosphatidylcholin (DMPC) phospholipid bilayer is studied by using molecular dynamics (MD).

Small-angle X-ray scattering (SAXS) is used to study the structure of a complex formed from DNA, calcium and DPPC. The effects of calcium on lipids are studied.

Ryanodine receptors (RyRs) are Ca(super ++) channels that control cellular functions. An estimation of the RyR2 ion diffusion constants and electrostatic interactions, in a self-consistent coherent formulation, is provided by the extended PNP.

A study of the uderpotential depostion (UPD) of Te monolayers onto Au electrodes from perchloric acid solution using electrochemical quartz microgravimetry (EQCM) and chronocoulometry is reported. Analysis of the current time data indicates that this process occurs by a two-dimensional instantaneous nucleation and growth mechanism, resulting in an ordered overlayer with a fractional coverage of ca. 0.41.

Three types of calcium carbonyl complexes are formed due to adsorption of CO on CaNaY at 85K. These three principle bands are formed in the carbonyl stretching region at 2185, 2167 and 2145 cm-1.

A study was conducted on two different soluble polymers where it is suggested that noncovalent interaction and cooperation between soluble macromolecules play key roles in controlling the growth of biominerals. The results suggest a novel and facile route toward biomimetic inorganic synthesis.

The equilibrium structure and potential-energy surface of calcium difluoride, CaF(sub 2) is determined from large-scale ab initio calculations using the coupled-cluster method, CCSD(T), in conjunction with basis sets of quadruple and quintuple zeta quality. The high-quality ab initio approach is applied to characterize the 3D potential-energy surface and vibrational-rotational energy levels of calcium difluoride.

A detailed investigation of the solvation structure of dilute Ca(super 2+) -and Sr(super 2+) -water solution and also Ca(super 2+) -methanol solution using a classical MD techniques and polarization potential models, is presented. The molecular dynamics (MD) results were coupled to electron scattering simulations in order to generate the Ca(super 2+) and Sr(super 2+) extended X-ray absorption fine structure (EXAFS) spectra.

(super 17)O magic angle spinning (MAS) and triple quantum magic angle spinning (3QMAS) NMR is used to show nonrandom distributions of the network-modifying cations Na and Ca in Ca-Na silicate glasses, by probing the atomic configuration around the nonbridging oxygens. Nonrandomness in Na-Ca mixing was observed in (super 17)O MAS and 3QMAS NMR where several nonbridging oxygen peaks such as Na-O-(super [4])Si, and mixed peaks are partially resolved.

Ultrasonic absorption spectra between 800kHz and 2GHz and sound velocities of aqueous solutions of calcium nitrate are measured at different salt concentrations and temperatures. The high-frequency ultrasonic relaxation is assumed to be due to the equilibrium between an outersphere ion complex and a contact ion pair.

Research is done on the reactivity of gas-phase ground-state calcium atoms with O2, which is reported from 296 to 623 K. In conclusion the RRKM theory, fitted to the experimental data, predicts the following expression for the rate coefficient from 140 to 1000 K and 10(super -5) to 10(super 3) Torr: log(k(sub rec, 0)/cm(super 6) molecule(super -2) s(super -1)) = -57.10 + 19.70 log T -- 3.410(log T)(super 2), k(sub rec, infinity) = 1.36 x 10(super -10) exp(-- 1020/T) cm(super 3) molecule(super -1) s(super -1), and Fc = 0.67.

The absorbance and the steady-state and time-resolved fluorescence responses to Ca(sub 2+) induced conformational changes within cod 111parvalbumin (C3P), which was labeled at cystein-18 with the fluorescent probes fluorescein, acrylodan or nitrobenzoxadiazole (NBD) is examined. The two probes produced poor responses indicating the difficulty associated with predicting the behavior of a labeled protein.

Monte Carlo simulation is used as a means to select calcium over sodium in a biological channel. The selectivity results from interplay between the volume exclusion effect due to the narrow channel diameter and the negative charge on the glutamates.