Theoretical investigation of the N → Sn coordination in (Me3SnCN)2

Abstract

The N → Sn coordination occurring in the (Me 3 SnCN) 2 dimer has been investigated using various computational methods and several theoretical tools possessing great interpretative potential. The dimer is formed by moving the C≡N fragment of the first Me 3 SnCN molecule close to the Sn atom of the second molecule and the resulting N → Sn coordination corresponds to that observed in the crystal structure of trimethyltin cyanide. The geometry of (Me 3 SnCN) 2 is optimized using the MP2 method and its 11 variants, and then it is compared with the reference geometry obtained at the CCSD level of theory. SCS-MP2 reproduces best the reference geometry of (Me 3 SnCN) 2 and its accuracy is close to that of the MP4 (SDQ) method. Two families of basis sets, namely the correlation-consistent basis sets proposed by Dunning and co-workers and the 'def2' basis sets developed by Ahlrichs and co-workers, are taken into account and their effect on the geometry of the dimer is examined in detail. The intermolecular interaction in (Me 3 SnCN) 2 has been analyzed using SAPT, NBO, QTAIM, and ELF. The results indicate that the (Me 3 SnCN) 2 dimer possesses a weak N → Sn coordination bond whose character is predominantly ionic. A value of −7.64 kcal/mol is proposed to be the best estimate of the interaction energy between the Me 3 SnCN molecules in the dimer.

Conformers of diheteroaryl ketones and thioketones: a quantum chemical study of their properties and fundamental intramolecular energetic effects

“…Fifth, the spin-component scaled variant of MP2 demonstrates poor accuracy in the calculated DE value for the cc-1b, which results in the wrong ordering of the cc-and tt-conformers. On the other hand, SCS-MP2 shows an improvement in DE for 1a over MP2, which in turn is in line with previous reports on the improved performance of SCS-MP2 in providing the structural and energetic description of conformations for molecules [50,51] and molecular complexes [52][53][54].…”

Hexacoordinated Tetrel‐Bonded Complexes between TF4 (T=Si, Ge, Sn, Pb) and NCH: Competition between σ‐ and π‐Holes

“…[25,26,38,98,99] Previous studies have confirmed the trend that the tetrel bond grows stronger as T becomes larger, [30,32,33,47,100] but that the effect levels off between Sn and Pb. However, there are a few works dealing with tetravalent Sn and Pb, and the noncovalent bonds they form with various bases.…”

“…Closely related to these interactions are those in which the bridging atom comes from the tetrel family (C, Si, Ge, etc). [16][17][18][19][20][21] There is a rapidly growing literature [22][23][24][25][26][27] that has provided a wealth of insights into the chemical and physical phenomena that underlie tetrel bonds. This larger number of substituents obstructs a clear passage of an approaching nucleophile toward the tetrel atom, [8] which can inhibit the formation of such a bond or at the least require a good deal of deformation so as to clear a space for the Lewis base.…”

N → Sn coordination in the complexes of tin halides with pyridine: A comparison between Sn(II) and Sn(IV)

“…As evidenced by ε elst in Table , the interaction between SnX n and py is determined to a great extent by electrostatic forces, providing at least 41.8% of the total attraction. The importance of electrostatics in N → Sn is supported by the results of our previous study of (Me 3 SnCN) 2 . The SAPT analysis of N → Sn coordination linking two Me 3 SnCN molecules proved that these molecules were held together mainly by electrostatic interactions.…”