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The solvation of a single NaCl molecule in water molecules is discussed using density functional theory. As we add H2O molecules, the distance between Na and Cl ions increases. Six H2O molecules are enough to make both the distances between Na and Cl ions with nearest O atoms (in H2O molecule) less than Na-Cl distance. Natural bond analysis (NBO) shows that absolute charges on Na and Cl ions decrease as we add H2O molecules with the absolute charge on Na ion slightly less than Cl ion. The energy gap increases and approaches the experimental energy gap of liquid water at 6.9 eV. Both Gibbs free energy and enthalpy are negative indicating that the reaction is spontaneous and exothermic. The enthalpy converges to the value of the solvation of both Na and Cl ions in water. The negative sign of the entropy indicates order reaction. The Raman vibrational spectra changes from the single vibrational mode at 341.93 cm−1 of NaCl molecule and three H2O molecule vibrational modes at 1584, 3863.9, and 3778 cm−1 to three multi bands centred at 500, 1600 and 3400 cm−1 for NaCl with 9 H2O molecules with the diminishing of Na-Cl vibration intensity.

Aerosol-assisted chemical vapor deposition (AACVD) technique is very precise implemented to fabrication of structured SrTiO3 and Sr1-xBxTiO3 thin films at doping ratio (x = 2, 4, 6 and 8) % at temperature 400 °C on a glass substrate. The X-Ray Diffraction (XRD) patterns illustrated that the SrTiO3 and Sr1-xBxTiO3 thin films have a polycrystalline nature and cubic structure, the detailed characterization of the films by X-ray diffraction (XRD), the Surface Morphology studied by using (AFM) and (SEM). Have been noticed from AFM measurement the Roughness and RMS were increased with increases doping ratio. The optical properties of SrTiO3 and Sr1-xBxTiO3 thin films have been studied at doping ratio (x = 2, 4, 6 and 8) % at rate (300-900) nm. The transmittance spectrum is characterized by the opposite behavior of the absorbance spectrum. The transmittance generally increases with the increase in the wavelength of radiation, at wavelengths with low energies while the absorbance decreased slowly at spectrum rate (300-900) nm i.e. in the visible region. The band gap (Eg) is decreased at (3.2 - 2.5) eV which indicates that the doping process has led to the emergence of localized levels in the region confined by the valence and conduction bands, led to a reduction in the photon energy required for direct electronic transitions to occur. Found the carriers concentration charge are holes of Sr1-xBxTiO3 thin films at doping ratio (x = 2, 4, 6 and 8) %. Many properties can be improved by adding impurities such as Boron (B) to the SrTiO3, which can be used in solar cells, electronic industries or thermoelectric generators by controlling the optical or structural properties of the material by controlling the materials and percentages of impurity, or through heat treatment of the material, such as annealing, for example or exposure to different temperatures.

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