Ibrahim Mahmoud A A, Saeed Rehab R A, Shehata Mohammed N I, Moussa Nayra A M, Tawfeek Ahmed M, Ahmed Muhammad Naeem, Abd El-Rahman Mohamed K, Shoeib Tamer
Computational Chemistry Laboratory, Chemistry Department, Faculty of Science, Minia University, Minia 61519, Egypt.
School of Health Sciences, University of KwaZulu-Natal, Westville Campus, Durban 4000, South Africa.
ACS Omega. 2023 Aug 30;8(36):32828-32837. doi: 10.1021/acsomega.3c03981. eCollection 2023 Sep 12.
For the first time, sigma (σ)- and lone-pair (lp)-hole site-based interactions of SF and SeF molecules in seesaw geometry with NH and FH Lewis bases were herein comparatively investigated. The obtained findings from the electrostatic potential analysis outlined the emergence of sundry holes on the molecular entity of the SF and SeF molecules, dubbed the σ- and lp-holes. The energetic viewpoint announced splendid negative binding energy values for σ-hole site-based interactions succeeded by lp-hole analogues, which were found to be -9.21 and -0.50 kcal/mol, respectively, for SeF···NH complex as a case study. Conspicuously, a proper concurrence between the strength of chalcogen σ-hole site-based interactions and the chalcogen's atomic size was obtained, whereas a reverse pattern was proclaimed for the lp-hole counterparts. Further, a higher preference for the YF···NH complexes with elevated negative binding energy was promulgated over the YF···FH ones, indicating the eminent role of Lewis basicity. The indications of the quantum theory of atoms in molecules generally asserted the closed-shell nature of all the considered interactions. The observation of symmetry-adapted perturbation theory revealed the substantial contributing role of the electrostatic forces beyond the occurrence of σ-hole site-based interactions. In comparison, the dispersion forces were specified to govern the lp-hole counterparts. Such emerging findings would be a gate for the fruitful forthcoming applications of chalcogen bonding interactions in crystal engineering and biological systems.
本文首次对跷跷板构型的 SF 和 SeF 分子与 NH 和 FH 路易斯碱之间基于 σ 和孤对电子（lp）空穴位点的相互作用进行了比较研究。静电势分析得出的结果表明，SF 和 SeF 分子的分子实体上出现了各种空穴，即 σ 空穴和 lp 空穴。从能量角度来看，基于 σ 空穴位点的相互作用具有出色的负结合能值，随后是 lp 空穴类似物，以 SeF···NH 络合物为例，其值分别为 -9.21 和 -0.50 kcal/mol。值得注意的是，硫族元素基于 σ 空穴位点的相互作用强度与硫族元素的原子大小之间存在适当的一致性，而 lp 空穴对应物则呈现相反的模式。此外，相对于 YF···FH 络合物，YF···NH 络合物具有更高的负结合能，这表明路易斯碱性起着重要作用。分子中原子的量子理论的迹象通常表明所有考虑的相互作用都具有闭壳层性质。对称适应微扰理论的观察结果表明，除了基于 σ 空穴位点的相互作用外，静电力也起着重要作用。相比之下，色散力则主导着 lp 空穴对应物。这些新发现将为硫族元素键合相互作用在晶体工程和生物系统中的丰硕应用开辟道路。
