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Electronic structure, Raman tensors, and resonance phenomena in a simple molecular model

M. Meyer, P. G. Etchegoin, E. C. Le Ru
2010 American Journal of Physics  
The model yields insight into resonance phenomena, symmetry-related aspects of Raman tensors, and the microscopic origin of the Raman effect itself.  ...  An example is the changes in the intrinsic symmetry of Raman tensors in molecules produced by resonance or near-resonance conditions.  ...  1 ͘ ប͑ k − 1 ͒ + ប − i⌫ ͪ, ͑12͒ where ␣ ij ͑͒ is the ij-component of the linear optical polarizability tensor at frequency and the parameter ⌫ models the resonant damping/broadening.  ... 
doi:10.1119/1.3271796 fatcat:r3hzgar6jnh4zn5tncoo4xduyq

External Field Effect on Electronic and Vibrational Properties of Carotenoids [chapter]

Nan Gong, Zuowei Li, Chenglin Sun, Zhiwei Men
2018 Progress in Carotenoid Research  
Resonance Raman spectroscopy is one of the most popular molecular spectroscopy methods.  ...  This review has significant importance in understanding the resonance Raman scattering, structural properties of polyenes, and the physics behind it.  ...  Conflict of interest The authors declare no conflict of interest. Thanks This review dedicates to our respectable tutor Z. W.  ... 
doi:10.5772/intechopen.78593 fatcat:76ixohzdd5fbjootqnvawvtqcm

A method for determining the magnitude of the Raman scattering matrix element for diamond-type crystals

E. Burstein, S. Ganesan
1965 Journal de Physique  
d'impuretés actifs en Raman.  ...  La mesure de la constante d'absorption de la bande induite devrait donc fournir des renseignements quantitatifs sur les éléments de la matrice de diffusion Raman du premier ordre.  ...  , transitions of the molecules lead to electric field induced absorption bands.  ... 
doi:10.1051/jphys:019650026011063700 fatcat:iyf27d7gyzcnnd7ty3vdmvjqqi

Threshold of a random laser based on Raman gain in cold atoms

William Guerin, Nicolas Mercadier, Davide Brivio, Robin Kaiser
2009 Optics Express  
We apply this idea to experimentally evaluate the threshold of a random laser based on Raman gain between non-degenerate Zeeman states and find a critical optical thickness on the order of 200, which is  ...  As a consequence, the random laser threshold is expressed as a function of this polarizability, which can be fully determined by spectroscopic measurements.  ...  Atoms are probed with a π-polarized (with perpendicular direction) probe beam, thus inducing ∆m F = ±1 Raman transitions.  ... 
doi:10.1364/oe.17.011236 pmid:19582036 fatcat:gbp7ru6btfhkfpe4kyqzq47s6y

Multiphonons resonance Raman scattering in Landau-quantized graphene [article]

Zi-Wu Wang, Zhi-Qing Li
2017 arXiv   pre-print
This behavior may be used to explain the changing shoulder of the Raman spectrum of optical phonon resonance scattering in experiments.  ...  The theoretical model could be expanded to analyze the fine structure of Raman spectrum in two-dimensional materials.  ...  This behavior may be used to explain the changing shoulder of the Raman spectrum of optical phonon resonance scattering in experiments.  ... 
arXiv:1711.11298v1 fatcat:udzo35wco5aqdfrhhbropmzjim

Inspecting chiral molecules by Raman optical activity spectroscopy

Václav Parchaňský, Josef Kapitán, Petr Bouř
2014 RSC Advances  
Raman optical activity (ROA) is a relatively new method combining the variability of scattering experiments with the structural sensitivity of chiral spectroscopy.  ...  Typically, ROA can be employed to determine absolute configuration (AC) of organic compounds, chiral metal complexes, and conformation of biologically relevant chiral molecules in solution.  ...  Acknowledgements This work was supported by the Czech Science Foundation (P208/11/0105, 13-03978S), Academy of Sciences (M200551205), and Ministry of Education (LH11033, 20/2014).  ... 
doi:10.1039/c4ra10416a fatcat:7s3kgd6ohrgtpgbw5hxcbuafrm

Intense chirality induction in nitrile solvents by a helquat dye monitored by near resonance Raman scattering

Jaroslav Šebestík, Filip Teplý, Ivana Císařová, Jan Vávra, Dušan Koval, Petr Bouř
2016 Chemical Communications  
A large induction of solvent chirality was observed in Raman optical activity spectra of a helquat dye in nitrile solvents.  ...  This effect was observable as an intense Raman optical activity (ROA) induced in acetonitrile, acetonitrile-d 3 , and liquid hydrogen cyanide solvents.  ...  As the last approximation, the empirical transition polarizability model (TPM) 22 where the solute and solvent are represented only by polarizable particles (Fig. S8, ESI †) was used.  ... 
doi:10.1039/c6cc01606e pmid:27087537 fatcat:bstqsuvchvauzhqk5opo56ta74

Ultrahigh Vacuum Optical Spectroscopy of Chemically Functionalized Graphene Nanoribbons [chapter]

A. Grüneis, B.V. Senkovskiy, A.V. Fedorov, M. Hell, S. Michel
2017 Reference Module in Chemistry, Molecular Sciences and Chemical Engineering  
. 4A indicate the six Raman active phonons as theoretically predicted by bond-polarizability theory.  ...  After Li doping, a reduction in the Raman intensity by a factor of $ 20 is observed which we attribute to Pauli blocking of the optical transition or the change of the resonance condition.  ... 
doi:10.1016/b978-0-12-409547-2.14168-x fatcat:ojrlkvp7jbgmxafotvvszr5ikm

Potential Application of h-BNC Structures in SERS and SEHRS Spectroscopies: A Theoretical Perspective

Sara Gil-Guerrero, Nicolás Otero, Marta Queizán, Marcos Mandado Alonso
2019 Sensors  
The quantum chemical simulations performed in this work point out that nanographenes embedded within hybrid h-BNC structures may serve as good platforms for enhancing the (Hyper)Raman activity of organic  ...  Static and dynamic (hyper)polarizabilities were calculated with coupled-perturbed Kohn-Sham theory (CPKS) and the linear and nonlinear optical responses of the complexes were analyzed in detail using laser  ...  Conflicts of Interest: The authors declare no conflict of interest.  ... 
doi:10.3390/s19081896 fatcat:i5jdeyb7dvcurjfvz2yvizcwx4

Pulse shaping and coherent Raman spectroscopy in condensed phases

Y. J. Yan, S. Mukamel
1991 Journal of Chemical Physics  
The limitations of the driven oscillator model are clarified, and generalized equations of motion, which hold for resonant and off resonant excitation, are derived.  ...  A microscopic theory for ultrafast coherent Raman spectroscopy of polyatomic molecules in condensed phases is developed.  ...  Off resonant Raman scattering is induced by the dependence of the electronic polarizability on the nuclear coordinates a = a(q) .  ... 
doi:10.1063/1.459938 fatcat:mqx4l5iohrazjbikriyade42ce

Two Spectroscopies in One: Interference of Circular Dichroism and Raman Optical Activity

Tao Wu, Guojie Li, Josef Kapitan, Jiri Kessler, Yunjie Xu, Petr Bour
2020 Angewandte Chemie  
Previously, we and other laboratories have reported an unusual and strong Raman optical activity (ROA) induced in solvents by chiral dyes.  ...  (VCD), [2] Raman optical activity (ROA) and many other techniques. [3] Quite recently, for example, enhanced VCD was pointed out as a useful tool for studies of protein fibrils associated with neurodegenerative  ...  Acknowledgements This work was funded by the Grant Agency (18-05770S (JKa and PB), 20-10144S (JKe), and 19-05974Y (TW)) and Ministry of Education (LTC17012, LM2018140, and  ... 
doi:10.1002/ange.202011146 fatcat:go3336odcjccrp72wrdpyp64fq

Light Scattering with Laser Sources [chapter]

S. P. S. Porto
1969 Light Scattering Spectra of Solids  
The selection rules obtained from group theory, the effect on the selection rules of optical activity in the crystal and the effect of simultaneous Raman and infrared activities of phonons for uniaxial  ...  CALLY, Raman spectra arise from the scattering of \\,)) light by an induced oscillating dipole, the inducing field being that of laser radiation of frequency wl: 1: =a];= (a 0 + a 1 coswMt) E 0 coswlt  ... 
doi:10.1007/978-3-642-87357-7_1 fatcat:zpjkl2hnj5cjdo3ux2wzqxjeoe

Population trapping and laser-induced continuum structure in helium: Experiment and theory

T. Halfmann, L. P. Yatsenko, M. Shapiro, B. W. Shore, K. Bergmann
1998 Physical Review A. Atomic, Molecular, and Optical Physics  
We report the observation of laser-induced structure ͑LICS͒ in the flat photoionization continuum of helium.  ...  A discussed theoretical model, incorporating significant dynamic Stark shifts, gives a quantitatively accurate description of the line profile for a wide range of pulse intensities.  ...  Unanyan, Institute for Physical Research of Armenian Academy of Sciences, Ashtarak, Armenia, for valuable help and discussions. M.S. and K.B. acknowledge support by the German Israeli Foundation.  ... 
doi:10.1103/physreva.58.r46 fatcat:eley235mcjbvnlbvbiosn3fs2m

Off‐resonant transient birefringence in liquids

Minhaeng Cho, Mei Du, Norbert F. Scherer, Graham R. Fleming, Shaul Mukamel
1993 Journal of Chemical Physics  
The homodyne-detected birefringence signal is directly compared with the coherent Raman signal. The relationship between off-resonant birefringence and spontaneous Raman experiments is discussed.  ...  By expanding the polarizability in powers of the nuclear coordinates and applying the Brownian oscillator model to the coordinate response function, we separate the birefringence signal into intra-and  ...  The optical nonlinear response function for the spin Boson model to arbitrary order in the radiation field and including an arbitrary (non-Condon) dependence of the transition dipole on nuclear coordinates  ... 
doi:10.1063/1.465256 fatcat:e6bhnn6wnzbvlfh2qo3ucjgb5e

Si/Ge elatform for lasers, amplifiers, and nonlinear optical devices based on the Raman Effect

Ricardo Claps, Dimitrios Dimitropoulos, Varun Raghunathan, Sasan Fathpour, Bahram Jalali, Bernard Jusserand, Carmen Mermelstein, David P. Bour
2007 Novel In-Plane Semiconductor Lasers VI  
The use of a silicon-germanium platform for the development of optically active devices will be discussed in this paper, from the perspective of Raman and Brillouin scattering phenomena.  ...  Moreover, new Raman-active branches and inhomogeneously broadened spectra result from optical phonon modes, offering new perspectives for optical device applications.  ...  Using the Bond-Polarizability Theory, for the case of in-plane Raman scattering from a Si 4 Ge 4 SL, the appearance of several Raman-active optical phonon modes has been demonstrated.  ... 
doi:10.1117/12.699524 fatcat:5k7zifv7dnemvfpbzts4hg4e5i
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