## Abstract

The independent systems approach for the circular dichroism (CD) of a magnetic dipole allowed transition of an achiral chromophore (A) in a chiral molecule leads to a perturbation expansion in terms of the electrostatic coupling operator V connecting the A states to those of the residual chiral framework C. The concomitant multipole expansion of V reduces the form of the CD to a power series in the inverse radial separation of A and C. Using the recently developed generalized selection rule procedure, the resultant expansion is analytically symmetry adapted to the point symmetries of the A and C chromophoric systems, with the explicit results presented for a wide range of symmetries. The results confirm that symmetry (particularly of A) is the principal determinant of the dominant CD mechanism, providing a rationale for the apparent inability of a unique mechanism to describe the CD activity of the wide range of A chromophore symmetries as found, for example, in transition metal complexes. Rigorous sector rules for the dominant mechanism for each A symmetry are derived. The general agreement with experimental behaviour consolidate the relevance of the independent systems approach.

Original language | English |
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Pages (from-to) | 173-193 |

Number of pages | 21 |

Journal | Chemical Physics |

Volume | 109 |

Issue number | 2-3 |

DOIs | |

Publication status | Published - 15 Nov 1986 |

Externally published | Yes |