Styrene as a monomer was emulsified in water using several magnetite nanoparticles concentration and pH values. Emulsified styrene drops were used as templates for polymerization, in presence of water soluble free radical initiator, and formation of composite particles. Styrene template drops stabilization was verified by light as well as scanning electron microscopy imaging, which ensured the participation of the particles in building up a mechanical barrier to stop oil drops coalescence. Furthermore, the produced polystyrene composites were strongly attracted to an external magnet. The difference in particles size as a function of pH was elucidated using zeta potential measurements, which indicated dominance of pH on the hydrophilicity of the particles and consequently the extent of emulsification, which in turn affected the size of the obtained microspheres. Under some circumstances, capsules were formed instead of particles. Thereby, it can be concluded that the magnetic microspheres are optimally formed at pH 2.3 independently of the magnetite content used.

A quantum chemical study was accomplished on the σ-hole interactions of the barely explored group IV elements, for the first time, in the absence and presence of the positively and negatively directed external electric field (EEF). The analyses of molecular electrostatic potential addressed the occurrence of the σ-hole on all the inspected tetrel atoms, confirming their salient versatility to engage in σ-hole interactions. MP2 energetic findings disclosed the occurrence of favorable σ-hole interactions within the tetrel bonding complexes. The tetrel bonding interactions became stronger in the order of C < Si < Ge < Sn for F–T–F3···FH complexes with the largest interaction energy amounting to −19.43 kcal/mol for the optimized F–Sn–F3···FH complex under the influence of +0.020 au EEF. The interaction energy conspicuously evolved by boosting the magnitude of the positively directed EEF value and declining the negatively directed EEF one. The decomposition analysis for the interaction energies was also executed in terms of symmetry-adapted perturbation theory, illuminating the dominant electrostatic contribution to all the studied complexes’ interactions except carbon-based interactions controlled by dispersion forces. The outcomes that emerged from the current work reported significantly how the direction and strength of the EEF affect the tetrel-bonding interactions, leading to further improvements in the forthcoming studies of supramolecular chemistry and materials science.

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In the current study, σ‐hole interactions of group IV–VIII element‐containing molecules in tetrahedral geometry with Lewis bases were comparatively scrutinized. The FSiF3, OPF3, NSF3, FClO3, and OArO3 molecules were devoted as Lewis acid centers to interact with NH3 and NCH Lewis bases. According to the results, the most significant σ‐hole interactions were ascribed to the FSiF3⋅⋅⋅ and FClO3⋅⋅⋅Lewis base complexes with interaction energy up to –29.74 kcal mol−1 in the case of the FSiF3⋅⋅⋅NH3 complex. Symmetry‐adapted perturbation theory‐based energy decomposition analysis (SAPT‐EDA) demonstrated that the electrostatic energy (Eelst) was the most prevalent force dominating the explored interactions, while the exchange energies exhibited unfavorable contribution. Quantum theory of atoms in molecules (QTAIM) and noncovalent interaction (NCI) results emphasized the closed‐shell nature for all the investigated complexes except FSiF3⋅⋅⋅NH3 complex that demonstrated a covalent nature. Crucially, the utilization of the positively‐ and negatively‐directed external electric field (EEF) led to amelioration and debilitation of the strength of the studied interactions, respectively. The present findings provide knowledge essential to further expanded applications in the fields pertinent to materials science and crystal engineering.