Assessment of density functionals and paucity of non-covalent interactions in aminoylyne complexes of molybdenum and tungsten [(eta(5)-C5H5)(CO)(2)M equivalent to EN(SiMe3)(R)] (E = Si, Ge, Sn, Pb): a dispersion-corrected DFT study

作者：Pandey Krishna K^*; Patidar Pankaj; Bariya Pankaj K; Patidar Sunil K; Vishwakarma Ravi

来源：Dalton Transactions, 2014, 43(26): 9955-9967.

DOI：10.1039/c3dt53632g

Electronic, molecular structure and bonding energy analyses of the metal-aminosilylyne, -aminogermylyne, -aminostannylyne and -aminoplumbylyne complexes [(eta(5)-C5H5)(CO)(2)M equivalent to EN(SiMe3)(Ph)] (M = Mo, W) and [(eta(5)-C5H5)(CO)(2)Mo equivalent to GeN(SiMe3)(Mes)] have been investigated at DFT, DFT-D3 and DFT-D3(BJ) levels using BP86, PBE, PW91, RPBE, TPSS and M06-L functionals. The performance of metaGGA functionals for the geometries of aminoylyne complexes is better than GGA functionals. Significant dispersion interactions between O center dot center dot center dot H, E center dot center dot center dot C(O) and E center dot center dot center dot H pairs appeared in the dispersion-corrected geometries. The non-covalent distances of these interactions follow the order DFT > DFT-D3(BJ) > DFT-D3. The values of Nalewajski-Mrozek bond order (1.22-1.52) and Pauling bond order (2.23-2.59) of the optimized structures at BP86/TZ2P indicate the presence of multiple bonds between metal and E atoms. The overall electronic charges transfer from transition-metal fragments to ligands. The topological analysis based on QTAIM has been performed to determine the analogy of non-covalent interactions. The strength of M equivalent to EN(SiMe3)(R) bonds has been evaluated by energy decomposition analysis. The electrostatic interactions are almost equal to orbital interactions. The M <- E sigma-donation is smaller than the M -> E pi-back donation. Upon going from E = Si to E = Pb, the M-E bond orders decrease as Si > Ge > Sn > Pb, consistent with the observed geometry trends. The M-E uncorrected bond dissociation energies vary with the density functionals as RPBE < BP86 < PBE < TPSS < PW91. The largest DFT-D3 dispersion corrections to the BDEs correspond to the BP86 functional, ranging between 5.6-8.1 kcal mol(-1), which are smaller than the DFT-D3(BJ) dispersion corrections (10.1-12.0 kcal mol(-1)). The aryl substituents on nitrogen have an insignificant effect on M-E-N bending. The bending of the M-E-N bond angle has been discussed in terms of Jahn-Teller distortion. The larger noncovalent interaction and smaller absolute values of.E (HOMO-LUMO) with the M06-L functional are responsible for lowering the M-E-N bond angle.

• 出版日期2014