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The overall rate constants for H-abstraction (k) from CHCHClCH and D-abstraction (k) from CDCDClCD by chlorine atoms in the temperature range 298-528.5 K were determined and are described by the expressions: k = (3.52 ± 0.21) × 10 exp(-184 ± 19/T) cm molecule s and k = (1.91 ± 0.16) × 10 exp(-185 ± 31/T) cm molecule s respectively. The results of the experiment show that the value of the kinetic isotope effect (k/k) for the overall rate constants is temperature independent and is equal to 1.85 ± 0.17. A theoretical examination of these reaction mechanisms revealed some unusual properties, such as negative values of the activation energy for the H-abstraction reaction from the secondary carbon atom. Moreover, it was proved that in the radical process of H-abstraction from the primary carbon atom of 2-chloropropane the created R-Cl···Cl complex is the most stable structure responsible for the value of the activation energy of this transformation.

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The overall rate constant for H‐abstraction (kH) from CH3CH2CH2Cl and D‐abstraction (kD) from CD3CH2CD2Cl by chlorine atoms is described by the formulas: kH=false(6.48−1.19+1.45false)×10−12·(T298)(1.810.28em±0.28em0.15)·exp(597±0.28em62)Tcnormalm3moleculnormale−1normals−1and kD=false(1.45−0.27+0.33false)×10−12·exp(801±62)Tcnormalm3moleculnormale−1normals−1, respectively. The results of the experiment show that the value of the kinetic isotope effect (kH/kD) for the overall rate constants is also temperature dependent in the temperature range of 298–550 K and can be expressed as kHkD=false(4.34−1.27+1.80false)·(T298)−0.88±0.26·expfalse(−1950.28em±0.28em105Tfalse). The titled reaction was also studied theoretically for the same range of temperatures and with both isotope substituents, just like in the experiment. The computations were made using the MP2 method and the aug‐cc‐pVDZ basis set. This paper presents detailed results relating to structural parameters of each of the compounds, complexes, and all energy stages important to the reaction mechanism analysis. It also describes all possible individual channels of the process and their feasibilities. In addition, a kinetic analysis of the process was carried out with branching ratio calculations. The results presented here have been compared with those discussed in a paper published earlier, in which the same process was investigated.