Abstract 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, consistent 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.
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Tetrahedral omnidirectional full-tensor gravitational wave detector
Abstract We propose a new tetrahedral configuration of three-axis inertial sensors, whose signals when combined create an isotropic sensitivity to gravitational waves. This arrangement provides total sky coverage and full-tensor measurements of the gravity gradient using only four test masses (TMs), compared to the six TMs of the previously studied TIGA and superconducting omnidirectional gravitational radiation observatory designs. Since weakly suspending a TM in all three directions is difficult due to the gravity bias, we also present the directional sensitivity plot for the case where only horizontal displacements are measured. This antenna pattern is no longer isotropic, and results in a maximum sensitivity to minimum sensitivity ratio of 2:1 in power. The full gravity gradient tensor can in this case still be reconstructed if the platform is sufficiently isolated from ground tilt.
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- Award ID(s):
- 1912627
- PAR ID:
- 10379539
- Date Published:
- Journal Name:
- Classical and Quantum Gravity
- Volume:
- 39
- Issue:
- 22
- ISSN:
- 0264-9381
- Page Range / eLocation ID:
- 225012
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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