The electronic structure and reactivities of Fe（CO）n （n = 3~5） addition to different fullerenes have been investigated through the first-principles calculations, and the results indicate that Fe（CO）3 and Fe（CO...The electronic structure and reactivities of Fe（CO）n （n = 3~5） addition to different fullerenes have been investigated through the first-principles calculations, and the results indicate that Fe（CO）3 and Fe（CO）4 can be adsorbed to the outside network of fullerene via hollow and bridge sites, respectively. Both of them have larger binding energy, but when Fe（CO）5 is adsorbed via the top site, the binding energy is relatively smaller. According to the directional curvature theory, the reactivities of Fe（CO）3 addition to the fullerenes are determined by KM of the ring center, and those of Fe（CO）4 addition by KD of the C–C bond curvature; while for Fe（CO）5, it presents weak reactivities in the addition reaction because of the larger volume effect. No matter whether the addition reaction takes place on the hollow or bridge site, the binding energies show a linear relationship with KD. This work further enriched the directional curvature theory and applied the isolobel analogy theory in the fullerene addition reactions.展开更多
The molecular geometries and electronic structures of the fullerene derivatives C36（OH）n（n = 1～2） have been investigated on the basis of density functional theory calculation at the B3LYP/6-31＋＋G＊ level.The ge...The molecular geometries and electronic structures of the fullerene derivatives C36（OH）n（n = 1～2） have been investigated on the basis of density functional theory calculation at the B3LYP/6-31＋＋G＊ level.The geometry optimization results indicate that the location of C2 atom is the most active site in the three potential adding patterns,and the C1 or C2 site has a larger binding energy than C3 for the addition reactions of C36（D6h） cage and OH radicals resulting from the larger curvature.The electronic structure calculation results disclose that the C2 site has larger electronic population in HOMO and larger spin density,and the addition reaction on the C2 site need overcome a lesser energy gap than that on the C1 or C3 site.Thus,the addition is controlled jointly by the curvature and the electronic factors.Besides,when two hydroxyls are added to the C36 surface,the C2 sites are also the most active locations.The most stable addition adduct of C36（OH）2 is the isomer which holds Ci symmetry,and the spin multiplicity seriously affects the stabilities of the adducts.展开更多
The cycloaddition reactions of NH to different bonds on C70 have been studied by the first-principles calculations.The results indicate that the reactivity of cycloaddition reactions is determined by the directional c...The cycloaddition reactions of NH to different bonds on C70 have been studied by the first-principles calculations.The results indicate that the reactivity of cycloaddition reactions is determined by the directional curvature,KD,and the larger binding energy of Eb on the bond C5-C？5 can be ascribed to the unique bond which can be treated as the shortest bond of（5.5）-SWCNT in the four [6,6] ring fusion bonds.This work also discloses that the energy gap of different spin states is decided by the electronic density,and that of the frontier obitals for the bond C5-C？5 is larger than the value for the C4-C？4 bond.Furthermore,the transition state investigation of the two bond addition reactions provides a reaction barrier of 11.10 kcal/mol for the NH cycloaddition to the C5-C？5 bond;whereas,the addition reaction on C4-C？4 is a spontaneous pathway.Herein,the dynamics effect illustrates the [2＋1] cycloaddition reaction on the equatorial C5-C？5 bond to be unfavorable.展开更多
基金Supported by the National Natural Science Foundation of China (No. 21073034)the State Key Laboratory of Structural Chemistry (No. 20090060)
文摘The electronic structure and reactivities of Fe（CO）n （n = 3~5） addition to different fullerenes have been investigated through the first-principles calculations, and the results indicate that Fe（CO）3 and Fe（CO）4 can be adsorbed to the outside network of fullerene via hollow and bridge sites, respectively. Both of them have larger binding energy, but when Fe（CO）5 is adsorbed via the top site, the binding energy is relatively smaller. According to the directional curvature theory, the reactivities of Fe（CO）3 addition to the fullerenes are determined by KM of the ring center, and those of Fe（CO）4 addition by KD of the C–C bond curvature; while for Fe（CO）5, it presents weak reactivities in the addition reaction because of the larger volume effect. No matter whether the addition reaction takes place on the hollow or bridge site, the binding energies show a linear relationship with KD. This work further enriched the directional curvature theory and applied the isolobel analogy theory in the fullerene addition reactions.
基金supported by the National Natural Science Foundation of China (No. 21073034)the Foundation of State Key Laboratory of Structural Chemistry (No. 20090060)
文摘The molecular geometries and electronic structures of the fullerene derivatives C36（OH）n（n = 1～2） have been investigated on the basis of density functional theory calculation at the B3LYP/6-31＋＋G＊ level.The geometry optimization results indicate that the location of C2 atom is the most active site in the three potential adding patterns,and the C1 or C2 site has a larger binding energy than C3 for the addition reactions of C36（D6h） cage and OH radicals resulting from the larger curvature.The electronic structure calculation results disclose that the C2 site has larger electronic population in HOMO and larger spin density,and the addition reaction on the C2 site need overcome a lesser energy gap than that on the C1 or C3 site.Thus,the addition is controlled jointly by the curvature and the electronic factors.Besides,when two hydroxyls are added to the C36 surface,the C2 sites are also the most active locations.The most stable addition adduct of C36（OH）2 is the isomer which holds Ci symmetry,and the spin multiplicity seriously affects the stabilities of the adducts.
基金supported by the National Natural Science Foundation of China (No.21073034)the State Key Laboratory of Structural Chemistry (No.20090060)
文摘The cycloaddition reactions of NH to different bonds on C70 have been studied by the first-principles calculations.The results indicate that the reactivity of cycloaddition reactions is determined by the directional curvature,KD,and the larger binding energy of Eb on the bond C5-C？5 can be ascribed to the unique bond which can be treated as the shortest bond of（5.5）-SWCNT in the four [6,6] ring fusion bonds.This work also discloses that the energy gap of different spin states is decided by the electronic density,and that of the frontier obitals for the bond C5-C？5 is larger than the value for the C4-C？4 bond.Furthermore,the transition state investigation of the two bond addition reactions provides a reaction barrier of 11.10 kcal/mol for the NH cycloaddition to the C5-C？5 bond;whereas,the addition reaction on C4-C？4 is a spontaneous pathway.Herein,the dynamics effect illustrates the [2＋1] cycloaddition reaction on the equatorial C5-C？5 bond to be unfavorable.
