Structural investigation of different element-based samarium-doped hydroxyapatites by using quantum mechanical methods and experimental analysis

In this thesis, three different element-based Samarium (Sm)-doped HAp nanostructures powder were studied experimentally and theoretically. For the samples to be synthesized experimentally, one of three different base elements was selected, including Mg, Zn, and Sr, at a constant value of 0.133 at. %, for each group. Sm was utilized as a co-dopant for all of the samples in the different groups at varying amounts of (0, 0.133, 0.266, 0.399, 0.532 and 0.665 at. %). For each group, a wet chemical synthesis was performed. The effects of changing the amount of Sm addition on the structural, thermal and biocompatibility in vitro properties were investigated. HAp phase (above 98% for all of the samples of each group) and beta-tricalcium phosphate β − TCP were both confirmed as the major phase and minor phase, respectively, by XRD, FT-Raman spectroscopy and the FTIR measurements. Both the crystallite size and crystallinity decreased as the anisotropic energy density increased. There was no obvious change in morphology caused by the introduction of Sm. The thermal stability of each sample was confirmed. It was found that the amount of Sm presents affected cell viability. Additionally, all of the samples of each group were modeled and theoretically characterized by using the DFT to obtain the calculation results for visualizing the structure-properties relations. Thus, the BS, DOS, BG and LAC for all of the molded sample groups were computed to study their electronic properties as well as shielding properties. The co-doping effect on these properties was seen. The BG continuously decreased for all of the samples. LAC increased with Sm concentration for all samples but decreased with increasing X-ray energy. The HAp samples can efficiently be used in radiation shielding and medical applications because they can considerably attenuate photons in the 5-30 keV range.