Firstly, it should be pointed out that, in the ground electronic state, two mirror pairs of stable, S, and metastable, M, structures can be optimized: one pair for the R (clockwise), and another for the S (counterclockwise) motor rotation direction, as illustrated in Figure . It is also worth to note that the operation chirality of the motor is governed by the chirality of its S form, while the chirality of the M isomer participating in a given rotation cycle is always opposite. Upon a look at the optimized S and M structures and their characteristic features depicted in Figure , one can immediately see the energy equivalence between the S and M forms of different chirality: an anticipated effect, given the chemical identity of these species. The ground-state relative energy of the metastable form is found at about 170 meV (3.9 kcal/mol), which resembles values reported for some known motors, and which assures thermodynamic equilibrium to be quantitatively shifted towards the stable isomer under the room-temperature conditions.