Strongly Bound π‐Hole Tetrel Bonded Complexes between H₂SiO and Substituted Pyridines. Influence of Substituents

Abstract

Ab initio calculation at the MP2/aug-cc-pVTZ level has been performed on the π-hole based N … Si tetrel bonded complexes between substituted pyridines and H 2 SiO. The primary aim of the study is to find out the effect of substitution on the strength and nature of this tetrel bond, and its similarity/difference with the N … C tetrel bond. Correlation between the strength of the N … Si bond and several molecular properties of the Lewis acid (H 2 SiO) and base (pyridines) are explored. The properties of the tetrel bond are analyzed using AIM, NBO, and symmetry-adapted perturbation theory calculations. The complexes are characterized with short N … Si intermolecular distances and high binding energies ranging between À 142.72 and À 115.37 kJ/ mol. The high value of deformation energy indicates significant geometrical distortion of the monomer units. The AIM and NBO analysis reveal significant coordinate covalent bond character of the N•••Si π-hole bond. Sharp differences are also noticed in the orbital interactions present in the N•••Si and N•••C tetrel bonds.

Enhancement of tetrel bond involving tetrazole-TtR3(Tt = C, Si; R = H, F). Promotion of SiR3transfer by a triel bond

“…This strength extends also to bonding to π-holes generated on Si 63,64 when in a trivalent situation as in F 2 SiO 23 or H 2 SiO 65 where the N⋯Si interaction with substituted pyridines exceeds 30 kcal mol −1 and the distance between the two atoms is essentially equal to the sum of their covalent radii. Like the σ-hole bonds discussed here, there is a large deformation energy, roughly 8 kcal mol −1 in these cases.…”

Strong Be−N Interaction Induced Complementary Chemical Tuning to Design a Dual‐gated Single Molecule Junction

“…[28][29][30][31][32][33] This bond shares several common features with other π-hole based non-covalent interactions, especially the chalcogen and tetrel bonds. [34,35] A substantial charge transfer from the Lewis base to the vacant p orbitals of Be of the X 2 Be molecule is one of the significant characteristics of beryllium bonds. [30] Frontera et al with a Protein Data Base (PDB) search showed the experimental evidence of π-hole beryllium-bond in biological systems.…”

“…[33] Numerous experimental and theoretical studies have been carried out on beryllium bonds concerning its physical nature, cooperativity and its usefulness in molecular recognition and solid-state chemistry. [34][35][36] A considerable amount of efforts have also been devoted on the beryllium bonded complexes between nitrogen bases and BeX 2 molecule (X=H, F, Cl, OH). [37][38][39][40] Very often in crystal engineering, nitrogenbases like substituted bipyrdines, diazines and other substituted pyridine-based bases like acridine and 4-dimethylaminopyridine are being used as the constituent molecules (as Lewis bases) of non-covalently bonded cocrystals which finds its application in the field of optoelectronic materials.…”

Sigma-Hole and Lone-Pair-Hole Site-Based Interactions of Seesaw Tetravalent Chalcogen-Bearing Molecules with Lewis Bases

“…In detail, the σ-hole was illustrated to be an electron-deficient site located opposite to the covalent bond. , Apparently, π-hole was announced to describe a perpendicular electron-deficient portion to a planar skeleton of a molecular system. − Afterward, lone-pair (lp) hole was launched to be in the mirror to the lp position. − Recently, radical (R • ) hole was found in an opposite direction to the single electron (R • ) . The electrophilic character of such holes enabled group IV–VIII elements to form spurious interactions with Lewis bases (LBs), dubbed as tetrel, − pnicogen, − chalcogen, − halogen, − and aerogen − bonds, respectively.…”