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<p>This work presents the first simulations of the full optical rotation (OR) tensor at coupled cluster with single
and double excitations (CCSD) level in the modified velocity gauge (MVG) formalism. The CCSD-MVG OR
tensor is origin independent, and each tensor element can in principle be related directly to experimental
measurements on oriented systems. We compare the CCSD results with those from two density functionals, B3LYP and CAM-B3LYP, on a test set of 22 chiral molecules. The results show that the functionals
consistently overestimate the CCSD results for the individual tensor components and for the trace (which is
related to the isotropic OR), by 10-20% with CAM-B3LYP and 20-30% with B3LYP. The data show that
the contribution of the electric dipole-magnetic dipole polarizability tensor to the OR tensor is on average
twice as large as that of the electric dipole-electric quadrupole polarizability tensor. The difficult case of
(1S,4S)-(–)-norbornenone also reveals that the evaluation of the former polarizability tensor is more sensitive
than the latter. We attribute the better agreement of CAM-B3LYP with CCSD to the ability of this functional to better reproduce electron delocalization compared with B3LYP, consistently with previous reports
on isotropic OR. The CCSD-MVG approach allows the computation of reference data of the full OR tensor,
which may be used to test more computationally efficient approximate methods that can be employed to
study realistic models of optically active materials. </p>
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THE OPTICAL ROTATION OF EPIMERIC α-HEXOSAMINIC ACIDS
