## 3 Results and Discussion
### Preparation and Characterization of Magnetic Chiral PMO NPs
In addition, the \({}^{13}\)C NMR spectrum of the chiral PMO NPs in Figure 10b gives clear evidence of the successful synthesis of these nanoparticles from ligand (**4**) because it shows all the characteristic peaks of the incorporated ligands between 10 and 66 ppm, in addition to the aromatic species, ranging from 122 to 147 ppm, and a characteristic carbonyl peak of the urea group at 167 ppm. These results clearly indicate the formation of silsesquioxane frameworks and further demonstrate the incorporation of organic units into the silica networks. FT-IR spectroscopy was employed for determining the chemical composition of chiral PMO NPs and magnetic chiral PMO NPs. Figure 11 compares the FTIR spectra of both systems to the ligand (**4**). Both systems were similar, displaying equivalent peaks that determine the organic content of the chiral-bridged organosilane ligand (**4**) in addition to the distinct absorbance peaks at 1023, 1100, and 1283 cm\({}^{-1}\), which can be assigned to Si-C vibrations. Moreover, the absorption bands at intervals of 3120-3700 cm\({}^{-1}\) in both curves b and c are assigned to the Si-OH stretching vibrations in the resulting silica network. The absorbance peaks at 2790-3100 cm\({}^{-1}\) are assigned to C-H stretching from both  
Figure 8: (**a**) Size distribution of chiral PMO nanoparticles (NPs) and (**b**) Size distribution of magnetic chiral PMO NPs. Figure 9: N\({}_{2}\) adsorption–desorption isotherms of (**a**) chiral PMO NPs and (**b**) magnetic chiral PMO NPs. chiral systems. The presence of the oleate group coating on the magnetite nanoparticles can be barely observed, since its C-H and C=C stretching bands overlap with the distinct IR bands of the original chiral ligand. The synthesis of chiral PMO NPs and magnetic chiral NPs was also evident by following the organic contents in the resulting system in comparison to the as-synthesized MNP-OA nanoparticles by thermogravimetric analysis (TGA). In both systems, a slight decomposition occurred in the temperature range of 50-100 \({}^{\circ}\)C that could have resulted from ethanol and water residues in the detected system, and the major decomposition process that occurred between 150 and 600 \({}^{\circ}\)C. In Figure 12 curve a, a total weight loss of 19.2% was detected with MNP-OA, whereas chiral PMO NPs afforded a total organic loss of 68.2% (Figure 12, curve b), compared with 75.1% with magnetic chiral PMO NPs (Figure 12, curve c). These findings confirm the successful incorporation of the chiral ligand and the magnetic cores besides the good thermal stability of the synthesized chiral systems. Circular dichroism (CD) spectra of chiral compounds are quite sensitive to their chemical and physical changes. From this spectroscopic method, we would be able to study and prove the chiral character of the as-synthesized chiral PMO NPs compared to a bare chiral bridged-silane ligand (**4**). As seen in Figure 13, the CD spectra of the free ligand (curve a) and the condensed ligand (curve b) are quite similar, with a slight absorbance shift that resulted from its entrapment within the silicate framework. Figure 11: FTIR analysis of (**a**) chiral ligand (**4**), (**b**) chiral PMO NPs, and (**c**) chiral magnetic PMO NPs. Figure 10: (**a**) Solid-state \({}^{29}\)Si CP-MAS NMR spectroscopy of chiral PMO NPs and (**b**) solid state \({}^{13}\)C CP-MAS NMR spectroscopy of chiral PMO NPs.