Quantum coherent control of π-electron rotations in a nonplanar Chiral molecule

The results of a theoretical investigation of coherent π-electron dynamics for nonplanar (P)-2,2′-biphenol induced by ultrashort linearly polarized UV pulses are presented. The coherent ring currents originate from an excitation of a pair of quasi-degenerate electronic states by an ultrashort linearly polarized UV laser pulse. The magnitudes of the electronic ring currents are expressed as the sum of expectation values of the corresponding operators in the two phenol rings (L and R rings). Here, L (R) denotes the phenol ring in the left (right)-hand side of (P)-2,2′-biphenol. For n electrons in (P)-2,2′-biphenol, there are four possible rotational patterns. The bond current of the bridge bond linking the L and R rings is zero for the symmetric coherent state, while it is nonzero for the antisymmetric coherent state.