Z.P.V.E, zero point vibrational energy
Probably, the higher dipole moment values in the different media justify
those results. When the dipole moments vectors for both forms in gas
phase are represented we observe that not only the magnitudes of both
forms are different but also their orientations and directions are
different, as it can be seen in Figure 2 . On the other hand,
the R(+) forms in both media present higher volumes despite the fact
that the dipole moments present lower values, as compared with the (S-)
forms. Perhaps, the different positions of only donor N-H group could
justify that S(-) form in solution has a higher dipole moment value than
the other one.