Generalized Susceptibility Theory. III. Spectral Properties of Extended Molecular Systems: Optical Rotation of Helical Polymers

Helical vinyl polymers bearing N-heterocycles substituent BINOL derivatives were synthesized. The specific optical rotation and circular dichroism spectra data show the obtained polymers can keep a prevailing helicity of backbone in solution.

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D. Macromolecules Optical rotation in helical polymers

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1967.0057 ◽

1967 ◽

Vol 297 (1448) ◽

pp. 141-149 ◽

Cited By ~ 2

Keyword(s):

Optical Rotation ◽

Theoretical Problem ◽

Helical Polymers ◽

Single Electrons ◽

Propagation Of Light ◽

Quantum Mechanical Theory ◽

Electric Polarizabilities ◽

Important Landmark ◽

Asymmetric Environment

Our knowledge of the circular dichroism of helical molecules like polypeptides and nucleic acids has advanced enormously in the last ten years, yet the theoretical problem of calculating the optical rotation of molecules with several coupled chromophores has a long history, going back to the beginning of this century. It starts when Oseen (1915) and Born (1933) developed the concept of coupled electronic oscillators in great detail to explain the propagation of light in crystals. After the development of the quantum theory by Rosenfeld (1928) and Kuhn (1932), chemists tended to stress the role of single electrons making transitions in an asymmetric environment as the main source of optical activity (Condon, Altar & Eyring 1937; Condon 1937). But the subject continued to develop (Boys 1934) and the next important landmark is Kirkwood’s famous quantum mechanical theory of coupled chromophores (Kirkwood 1937). He showed how the Coulomb interaction between electronic transitions in neighbouring, but non-overlapping, parts of a molecule gave rise to new terms in the rotatory dispersion, which were proportional to the electric polarizabilities of the groups. Kirkwood’s final formulae were remarkably like those of the old classical theory. Now there is a pause of nearly twenty years until Moffitt (1956 a, b ) and Kirkwood’s (Fitts & Kirkwood 1956, 1957) brilliant work revived interest in the optical rotation of polymers. His theory laid a sure foundation for all the advances which have been made since his time and came at a most opportune moment.

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ELECTRONIC POLARIZABILITIES OF DIHYDRATED URANYL ACETATE UO2(H3CCOO)2.2H2O IN AQUEOUS SOLUTION

Periódico Tchê Química ◽

10.52571/ptq.v15.n30.2018.658_periodico30_pgs_654_659.pdf ◽

2018 ◽

Vol 15 (30) ◽

pp. 654-659

Author(s):

F. J. S. LIMA ◽

L. H. M. da COSTA ◽

A. O. da SILVA

Keyword(s):

Aqueous Solution ◽

Spectral Properties ◽

Electronic Configuration ◽

Research Area ◽

Uranyl Acetate ◽

Intermolecular Electron Transfer ◽

Visible Radiation ◽

Electron Pairs ◽

Molecular Systems ◽

Donor Species

Electronic studies in molecular systems have been used to evaluate the possibility of improvements in the efficiency of physicochemical processes of interest in electronic devices. We have studied complex molecular systems prototypes in our research area, especially involved in intra- and intermolecular electron transfer. In this work, we performed the spectral recording of uranyl acetate dihydrate in aqueous solution to characterize its spectral properties, related to the deformation of the electronic configuration, against the incidence of uv-visible radiation, in order to functionalize the spectral properties of uranium, by the insertion of donor species of electron pairs. For this we evaluate the electronic polarizabilities, by the use of the program POLAZ-F2.

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Probing vacuum-induced coherence via magneto-optical rotation in molecular systems

Physical Review A ◽

10.1103/physreva.93.063826 ◽

2016 ◽

Vol 93 (6) ◽

Cited By ~ 3

Author(s):

Pardeep Kumar ◽

Bimalendu Deb ◽

Shubhrangshu Dasgupta

Keyword(s):

Optical Rotation ◽

Molecular Systems

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Chirality analysis of helical polymers

Chemistry Teacher International ◽

10.1515/cti-2020-0009 ◽

2020 ◽

Vol 0 (0) ◽

Author(s):

Tamaki Nakano ◽

Adriana Pietropaolo ◽

Masahiro Kamata

Keyword(s):

Optical Rotation ◽

Polymeric Materials ◽

Helical Conformation ◽

Cd Spectra ◽

Chiroptical Properties ◽

Helical Polymers ◽

Exciton Coupling ◽

Related Information ◽

Unit Model ◽

Wide Range

AbstractOptically active macromolecules, having a preferred- or single-handed helical conformation, play important roles in polymeric materials and in life. This article presents how helical polymers can be assessed from a view of chirality. These assessments, based on optical rotation (OR) and circular dichroism (CD) spectral measurements with associated information, include theoretical spectral calculations as well as chromatographic resolution. Specific applied examples are discussed for poly(9,9-dioctylfluorene-2,7-diyl) and derivatives, stereoregular polyolefins bearing centers of chirality in the side chain, isotactic poly(triphenylmethyl methacrylate), and π-stacked poly(dibenzofulvene). For more convincing establishment of a helix, it is important to correlate chiroptical properties with related information such as molar-mass effects, temperature effects, and chemical transformation effects on the properties. Helices of the polyolefins and poly(TrMA) were confirmed considering these aspects. In addition, comparison of chiroptical properties between the polymer in question and a monomeric unit model compound generally helps to confirm a helix. There are no general, reliable methods to quantify helical sense excess. On the other hand, absolute helical sense can be determined by comparing experimental and theoretical CD spectra as well as considering exciton coupling effects in CD spectra. The former method can be more generally applied for a wide range of polymers as far as a good model for calculations is designed, while the latter can be more conveniently and empirically applied for a certain class of polymer structures that are suited to exhibit exciton coupling without using computers.

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