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As seen in experiments with poly(3‐hexylthiophene), substitution of hydrogen with deuterium on the main chain alone decreases crystallinity. To understand this effect, a general formalism for analysis of the dipole moments and polarizabilities incorporating quantum nuclei, is developed. The formalism, based on quantum dynamics of the proton/deuteron and on the perturbative analysis of the dipole interaction energy, accounts for the anharmonicity of a potential energy surface and for the anisotropy of molecular dipole moments. The formalism is implemented within the Discrete Variable Representation and the Density Functional Theory describing, respectively, the quantum proton/deuteron on the thiophene ring and the electronic structure of the 27‐atom model polymer chain, embedded into a larger crystalline environment. The isotope effect is mainly attributed to the differences in the zero‐point energy of the CH/CD bonds and to the isotope‐dependence of the dipole‐dipole inter‐chain interactions.
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Spectroscopy of Mesons Produced by Linearly Polarized Photons
A formalism for the experimental analysis of mesons produced by a beam of linearly polarized photons is presented. This formalism introduces a more general use of the reflectivity operator. The goal is to recognize resonances in cross-sections, their associated quantum numbers, and production mechanisms by performing partial wave analysis of multiple-meson final states.
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- Award ID(s):
- 2110797
- PAR ID:
- 10528706
- Publisher / Repository:
- Symmetry 2023, 15(11), 2018; https://doi.org/10.3390/sym15112018
- Date Published:
- Journal Name:
- Symmetry
- Volume:
- 15
- Issue:
- 11
- ISSN:
- 2073-8994
- Page Range / eLocation ID:
- 2018
- Subject(s) / Keyword(s):
- meson spectroscopy amplitude analysis polarized photons reflectivity
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3390/sym15112018
