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A systematic investigation on the H‐abstraction reactions of 8 carbene radical anions with CCl3H has been performed theoretically using the popular DFT functional BHandHLYP/aug‐cc‐pVTZ/RECP level of theory. As a result, our studies strongly suggest that the reactivity of the title reactions (CX1X2•− + CCl3H) present increase in the order: CHI•− < CHBr•− < CHCl•− < CHF•− for first halogen CHX•− and CCI2•− < CBr2•− < CCl2•− < CF2•− for second halogen CX2•−, more important, the reactions of the former exhibit more activity than those of corresponding the latter. Moreover, based on the NBO analysis, the Activation Strain model analysis and the correlations analyses of activation barrier with both PA and IE, respectively, we further confirm over the conclusion. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011 [ABSTRACT FROM AUTHOR]

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Abstract: Ab initio calculations of the two title reactions have been made to compare reactivities of OCS and CS2 toward a nucleophile, . MP2/6-311++G(d, p) geometry optimizations on the singlet potential energy surface have demonstrated that respective channels start from key intermediates and have revealed that multistep paths give the most favorable products: (1) +OCS→H2NS− +CO; (2) +OCS→HS− +HNCO; (3) +OCS→NCS− +H2O; (4) +OCS→NCO− +H2S; (5) +CS2 →NCS− +H2S; (6) +CS2 →HS− +HNCS. Furthermore, to get more reliable energetic data, single-point calculations are carried out at CCSD/6-311++G(d, p) level. The calculated result is consistent with the measured large rate constant in experiment. A comparison of reaction mechanisms is offered between +OCS and +CS2. [ABSTRACT FROM AUTHOR]

Abstract: The reactivity of X(3P) (X=Ge, Sn, Pb) with N2O(X1Σ) on both singlet and triplet potential energy surfaces have been investigated at the B3LYP level of theory. To accurately evaluate the activation barrier and reaction energy, the coupled cluster single point calculations using the B3LYP structures is performed. The calculated results are in good agreement with experimental observations. The (X=Ge, Sn, and Pb) reactions that Arthur Fontijn has been observed are spin-forbidden for formation of ground state products in the experiments. The present paper is discussed with the aid of the direct abstraction (DA) mechanism (also called the surface crossing model), a correlation argument based on separated fragments X+O+N2 can explain the inefficiency of the (X=Ge, Sn, and Pb) reactions at 298K by the need to switch electron configurations along low-energy adiabatic paths from ground-state reactants to energetically accessible product states. [Copyright &y& Elsevier]