In the work [1] it is shown that the equation (1), σ = ξ C* + γ, holds for surface tension σ of liquids with π-conjugated planar molecules. In Eq. (1) C* = V-2/3 (1 - T/Tc) ΔE × 10-5 (Nm-1mol-1/3), where the values V, T, and Tc are molar volume, temperature and critical temperature of a liquid, respectively. ΔE is the calculated (by the DFT B3LYP method with the 6-31G basis set) binding energy per one of the two molecules forming dimmer and belonging respectively to the surface liquid layer and the nearest neighboring one. It was found that the values of ξ and γ are equal to 0.893 (mol1/3) and 26.01 (Nm-1) respectively. The quantity γ describes the attraction between the molecules of the surface layer (due to the formation of the planar surface π-conjugated electronic system). In the present work we consider the influence of πσ*-hyperconjugation arising when σ* MOs of the CH bonds of the methyl groups (see the compounds presented in the Table) conjugate (and enter) the above surface π-electronic system. The main results of our study are given in Figure 1. One can see that the mentioned hyperconjugation leads to the parallel shift the linear dependence (see Eq. (1)) towards the region with the new lower value of γ.figureFig. 1. Correlation between the experimental values of σ and the calculated values of C*