On complex formation in equimolar chloroform–benzene solution: A revisit by molecular dynamics simulation and orientational correlation states superposition

Abstract

We present molecular dynamics simulations of the seventeen-atom system of chloroform equimolar in benzene on the basis of a previously proven Fortran code, Lennard–Jones potential parameters, fractional atomic charges, and complete molecular structure data between 248 and 498 K at a common density. Specifically, the generated l = 1 orientational auto-correlation functions of the tumbling and spinning–tumbling motions of chloroform in its benzene solution are combined, by established group-theoretical principles, to three linear combinations that quantitatively characterize for the benzene-dissolved chloroform molecules the time evolution of the average direction of their average rotation axis as well as that of the mean rotation angle around it. Based on these findings we conclude, first, that the probability density function of the average rotational motion of the dissolved chloroform molecules follows a memory-less process (Markoffian), second, that a previously proposed 1:1 chloroform–benzene complex, with the H atom of the C–H bond of its chloroform moiety pointing to the center of the plane of an adjacent benzene species, has a near-vanishing probability to prevail in the solution.