Correlating net charges and the activity of bis(imino)pyridylcobalt complexes in ethylene polymerization

The Catalytic Activities of Carbocyclic Fused Pyridineimine Nickel Complexes Analogues in Ethylene Polymerization by Modeling Study

“…The electron donating and withdrawing ability of substituents describes the electronic effect [11,12], while the steric effect is actually associated with bond length, bond angle, size of the substituents, and atomic radii of transition metal [13][14][15]. In preceding reports, the catalytic activities for Fe, Co and Ni complex systems are investigated quantitatively from the perspective of the electronic effect by the correlation with effective net charge on the central metal atom (Q eff ) [16][17][18], activities for Fe, Co and Ni complex systems are investigated quantitatively from the perspective of the electronic effect by the correlation with effective net charge on the central metal atom (Qeff) [16][17][18], Highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy gaps (Δε) between complex and ethylene [19], and the energy difference between the two spin states (ΔE) [19], respectively.…”

Correlating Cobalt Net Charges with Catalytic Activities of the 2‐(Benzimidazolyl)‐6‐(1‐aryliminoethyl)pyridylcobalt Complexes toward Ethylene Polymerization

“…All structures of the studying model complexes are optimized by the density functional theory calculations using DMOL3 program . Double‐numerical basis sets with polarization functions (DNP) basis sets and GGA‐type BP exchange‐correlation functional are chosen to describe the geometry and energy combined with effective core potentials, which the convergence criteria for SCF calculations and the criteria for the geometry optimization were the same based on our previous studies . The charge values on cobalt atoms of all complex pre‐catalyst are obtained after the structure optimized by DFT calculation through different charge distribution methods.…”

“…This is consistent with the observation by their analogous iron complexes [34] and other complex systems. [41] To clarify correlations between effective net charges and catalytic activities, the data in Table 2 are transformed into Figure 1 with charged obtained by QEq method. Meanwhile, Figure S1 by Mulliken method and S2 by Hirshfeld method are illustrated in Supporting Information, respectively.…”

“…[ 34,41] Figure 2 shows the correlation between the effective net charges and catalytic activities for complexes 7-11 at doublet (D) and quartet (Q) obtained by QEq method. In general, the observed correlation by QEq results well assembles the tendency of catalytic activities and effective net charges for complexes 7-11.…”

Quantitative Structure-Thermostability Relationship of Late Transition Metal Catalysts in Ethylene Oligo/Polymerization

“…As a result, the quantitative structure-property relationship (QSPR) approach has proven to be useful. In our previous studies, the relationship between the structure of a catalyst and its catalytic activity was investigated by molecular modeling, which successfully predicted the catalytic activities of late transition metal complex precatalysts toward ethylene oligo/polymerization, through electronic effects [38][39][40][41] or both from electronic and steric effects [42,43]. Regarding the influence of the catalyst structure on its thermal stability, several possible factors were proposed by previous experimental research [19,[24][25][26][29][30][31][32][33][34][35][36].…”