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The mechanism of C–H bond of CH 4 activation catalyzed by VO 2 + ( 1 A 1 / 3 A′) has been investigated by using density functional theory (DFT) at the CCSD/6-311G(2d,p)//B3LYP/6-311G(2d,p) level. According to our calculation results, the four channels have been well-established and the reactivity patterns on the singlet and triplet PESs are almost similar. And the reaction proceeds in three distinct manners yielding the [V(OCH 2 ) + + H 2 O] products, the [V(OH 2 ) + + CH 2 O] products, the [OV(OCH 2 ) + + H 2 ] products and the [VO + + CH 3 OH] products. Specially, the crossing points (CPs) between the different PESs have been located by means of the intrinsic reaction coordinate (IRC) approach used by Yoshizawa et al., and corresponding minimum energy crossing points (MECPs) that we obtained by the mathematical algorithm proposed by Harvey et al. has also been employed. In addition, the frontier molecular orbital interaction analysis about 1 TS1, 3 TS1, 1 TS4 and 3 TS4 are used to gain useful information about the C–H bond of CH 4 activation by VO 2 + . [ABSTRACT FROM AUTHOR]

The mechanism of HH σ bond activation catalyzed by VO [ABSTRACT FROM AUTHOR]

Abstract: The gas-phase reaction of activation of C–C bond of C2H4 by VO2 + (1A1/3A′) has been investigated using density functional theory at the B3LYP/6-311++G(3df,3pd)//6-311G(2d,p) level. The calculation results show that the reaction experiences rearranging process. This is a typical case of TSR (two-state reactivity) for which a crossing point is located. In addition, the orbital interaction analysis of C–C double bond activation is carried out by fragment molecular orbital method. The results indicate that the orbital interaction mode of the C–C bond activation by the “early” transition metal oxide ion VO2 + is characteristic, as is compared with the DCD model and the CrO2 + +C2H4 system. [Copyright &y& Elsevier]

Abstract: A systematic theoretical study of the reaction NO2(2A1)+CO(1∑+)→NO(2∏)+CO2(1∑g +) catalyzed by Ti+ has been investigated by means of UB3LYP/6-311+G(2d) level. Our calculated results sharply reveal that both NO2(2A1)+Ti+(X4F)→NO(2∏)+TiO+(X2Δ) and TiO+(X2Δ)+CO(1∑+)→Ti+(X4F) + CO2(1∑g +) are spin-forbidden reactions. The minimum-energy crossing points (MECPs) that are involved have been characterized at the same level and the possible spin inversion processes are discussed using the intrinsic reaction coordinate (IRC) approach. [Copyright &y& Elsevier]