A study of the three-dimensional structure of aminodiene molecules by the spectroscopy of intermolecular interactions

Bakhshiev, N. G.; Perekalin, V. V.; Kasymova, M. K.; Kvitko, S. M.

doi:10.1007/bf00524583

Cited by 18 publications

(34 citation statements)

References 1 publication

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“…Thus, for the applications being discussed here the molecule mass must not significantly exceed 10 3 atomic units and their length -some 10Å. For such compounds the constant electric dipole moment is usually on the order of 1 − 10 D [11,14,15]. Therefore the alignment parameter achieved with the nearly breakdown dc field E 0 can hardly exceed the value about unit, even in the most electrically resistant solvents [16].…”

mentioning

confidence: 99%

Optical switching and inversionless amplification controlled by state-dependent alignment of molecules

Popov¹,

Slabko²

2005

J. Phys. B: At. Mol. Opt. Phys.

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We propose a method to achieve amplification without population inversion by anisotropic molecules whose orientation by an external electric field is state-dependent. It is based on decoupling of the lower-state molecules from the resonant light while the excited ones remain emitting. The suitable class of molecules is discussed, the equation for the gain factor is derived, and the magnitude of the inversionless amplification is estimated for the typical experimental conditions. Such switching of the sample from absorbing to amplifying via transparent state is shown to be possible both with the aid of dc and ac control electric fields.PACS numbers: 42.70.Hj Amplification of light is determined by the difference between the net absorbtion and stimulated emission of radiation. Usually, this requires larger population of the upper quantum state then the lower one that are coupled by the induced transitions. However, the amount of absorbed and emitted photons depend not only on the populations of the resonant energy levels but also on the probabilities of the induced transitions and on distribution of the populations over the energy-degenerated states. Therefore, the inversion of population is, generally speaking, only a special case, in which the amount of the emitted light prevails over the absorbed one. Based on this fact, a variety of realizations of amplification without population inversion (AWI) was proposed in the early years of quantum electronics. Such possibility based on a possible difference in velocity distribution in upper and lower states was discussed in [1]. Nonreciprocity of probabilities of induced emission and absorbtion caused by nonlinear interference affect in the field of the auxiliary radiation was investigated for two-level atoms in [2] and for three-level systems in [3]. Corresponding AWI at transitions of neon was predicted and analyzed in details in [4] and proved in the experiments [5]. The asymmetry in the lineshape of net emission and absorption at the transitions to the autoionizing states and related possibility of AWI was considered in [6]. A possible AWI in dichroic molecules was pointed out in [7]. The feasibility of AWI of short pulses in three-level system was considered in [8]. A review of later publications on AWI is given in [9]. An asymmetry in absorption and emission lineshape of two-level system caused by its interaction with a thermostat is discussed in recent publication [10]. In this paper we propose and discuss a method of achieving lasing without population inversion by the anisotropic molecules. It bases on selective alignment and consequent decoupling the lower-state molecules from the polarized resonant radiation, while the upper-state molecules remain amplifying this radiation through its stimulated emission.In electrodipole approximation, the probability of induced transitions between levels m and g, W mg , depends on the factor d mg cos θ, which is the projection of the electrodipole transition matrix element on a direction of a vector of a resonant oscill...

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confidence: 99%

Optical switching and inversionless amplification controlled by state-dependent alignment of molecules

Popov¹,

Slabko²

2005

J. Phys. B: At. Mol. Opt. Phys.

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“…The electronic transition frequency of the dye molecule as a function of the reactive field of the solvate can be written (1) as ‡ : † In thermodynamics it may be called "the free energy of the system." ‡ For simplicity, we will consider the electronic transition with a constant dipole moment of the dye molecule changing its magnitude rather than orientation.…”

Section: Field Diagram Of a Polar Solutionmentioning

confidence: 99%

Inhomogeneous Broadening of Electronic Spectra of Dye Molecules in Solutions

Nemkovich

Рубинов

Томин

Topics in Fluorescence Spectroscopy

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It is well known in spectroscopy of complex organic molecules that the large width of their absorption and emission bands is largely due to the existence of a continuous set of vibrational sublevels in each electronic state. The spectroscopic properties of dye molecules in solution are in addition influenced by the surrounding medium.(1-3) For several decades it had been believed that because of the fast energy exchange between the vibrational sublevels the fluorescence spectrum of organic dye in solution was independent of the frequency of the exciting light. In 1970 it was shown (4) for the first time that apart from molecular vibrations there is another cause of the substantial broadening of electronic spectra of organic molecules in solution, namely, the fluctuations of the structure of the solvation shell surrounding the molecule. The variation of the local electric field caused by the fluctuation of the shell structure leads to a statistical distribution of the frequencies of the electronic transitions of the molecules and, therefore, to inhomogeneous broadening of the dye spectrum.This broadening was experimentally demonstrated (4)(5)(6) from the dependence of the fluorescence spectrum of a dye solution on the exciting radiation frequency at 77°K. Later, Personov et al.(7) observed inhomogeneous broadening of electronic spectra from frozen solutions of complex molecules at lower (liquid helium) temperatures. It was shown that at liquid helium temperatures discrete fluorescence spectra of complex molecules with

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“…If the 1^ê xcited fluorophore has a high dipole moment, as in the case of tryptophan [7], this broadening could increase the width of absorption spectra by 300-500 cm-1 [34,35]. The most significant contribution to this type of broadening is caused by dipole-dipole interactions [26]. Such distributions are the origin of the red-edge effects [7,9].…”

Section: Differences In Na+ or K+-containing Buffersmentioning

confidence: 99%

“…Protein dynamics can be studied by observation of time dependent shifts of the fluorescence spectra as well as the time dependence of other spectroscopic effects of dipolar relaxation. If a system is described by a single dipolar relaxation time, rp, the shift of spectra with time should be exponential, and in principle the value of z* can be determined [26]. In practice the determination is complicated by a non exponential emission decay, which was also found in the case of Na,K-ATPase (see Table 1).…”

Section: Dipole-relaxational Dynamicsmentioning

confidence: 99%

Fluorescence spectroscopic studies on equilibrium dipole-relaxational dynamics of Na,K-ATPase

Demchenko

Apell

Stürmer

et al. 1993

Biophysical Chemistry

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Intramolecular dynamics in Na,K-ATPase molecules have been studied by ultraviolet fluorescence spectroscopic methods: determination of temperature-dependent shifts in steady-state spectra, site-selective red-edge effects and their temperature dependence, and time-resolved emission decay as a function of excitation and emission wavelengths. The combination of these methods allows the characterization of the dipolar-relaxational mobility in the environment of the tryptophan residues. Our results show that the mean dipolar-relaxational time is of the order of one nanosecond at room temperature. This is much faster than what is usually observed in globular proteins. The fast dynamics of the protein dipoles are rapid enough so that the dipoles are in dielectric equilibrium during the slower ion transfer processes; this may have important functional consequences.

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A study of the three-dimensional structure of aminodiene molecules by the spectroscopy of intermolecular interactions

Cited by 18 publications

References 1 publication

Optical switching and inversionless amplification controlled by state-dependent alignment of molecules

Optical switching and inversionless amplification controlled by state-dependent alignment of molecules

Inhomogeneous Broadening of Electronic Spectra of Dye Molecules in Solutions

Fluorescence spectroscopic studies on equilibrium dipole-relaxational dynamics of Na,K-ATPase

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