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61.
The absorption spectrum of the 16O3 isotopologue of ozone was recorded in the 7000–7920 cm?1 region by using high sensitivity CW-Cavity Ring Down Spectroscopy (αmin  10?10 cm?1). This report is devoted to the analysis of the 7300–7600 cm?1 region dominated by four A-type bands: 6ν1 + ν3 centred around 7395 cm?1, 3ν1 + 5ν2 + ν3 and 2ν1 + 4ν2 + 3ν3 lying in the 7450 cm?1 region and 5ν1 + 2ν2 + ν3 centred around 7579 cm?1. 213 transitions of the 6ν1 + ν3 band were assigned and the corresponding line positions were modeled using an effective Hamiltonian including a Coriolis resonance interaction between the (601) upper state and a A-type dark state. The two very close 3ν1 + 5ν2 + ν3 and 2ν1 + 4ν2 + 3ν3 bands were analysed using a similar effective Hamiltonian scheme involving the anharmonic resonance coupling between the (351) and (243) states. For these two bands, 304 transitions were assigned. The modelling also includes a first Coriolis resonance interaction between the (351) bright state and the (530) dark state, and a second one between the (243) bright state and the (144) dark state. In the 7579 cm?1 region, 205 transitions of the 5ν1 + 2ν2 + ν3 band were assigned and modelled taking into account the Coriolis resonance interactions between the (521) upper state and the (700), (342) and (280) dark states.The dipole transition moment parameters of the four analysed bands were determined by a least-squares fit to the measured line intensities. For the studied band systems, the effective Hamiltonian and transition moment operator parameters were used to generate line lists provided as Supplementary Materials.  相似文献   
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Continuing the systematic study of ozone high-resolution infrared spectra, we present in this paper the measurements and analyses of line positions for the 18O16O18O isotopomer. In the range 900-5000 cm−1, corresponding to the observed spectra, 15 bands are analysed: ν1, ν3, ν2+ν3, ν1+ν2, 2ν3, ν1+ν3, 2ν1, ν2+2ν3, ν1+ν2+ν3, 3ν3, 2ν1+ν3, ν2+3ν3, ν1+3ν3, ν1+ν2+3ν3, and 5ν3. As in the case of 16O3, 18O3, and 16O18O16O, the analysis of these bands is performed using effective rovibrational Hamiltonians for nine polyads of interacting upper vibrational states. To correctly reproduce all observed transitions, we have to account for resonance perturbations due to 13 “Dark” states: (0 3 0), (0 4 0), (2 1 0), (0 3 1), (1 0 2), (0 4 1), (1 1 2), (3 1 0), (0 3 2), (0 0 4), (3 2 0), (0 1 4), and (0 4 2). We present the range of observed transitions, the results for spectroscopic parameters (vibrational energy levels, rotational and centrifugal distortion constants, and resonance coupling parameters), as well as the statistics for rovibrational energy levels, calculations and measurements. A comparison of observed band centres with those predicted from an isotopically invariant potential function is discussed. The RMS deviation between predicted and directly observed band centres is ≈0.03 cm−1 up to 3000 and ≈0.25 cm−1 for all 16 bands up to 5000 cm−1.  相似文献   
65.
A series of complexes of chitosans of various molecular weights (3000–150000) with copper, iron(II), and zinc sulfates were examined. Participation of amino groups of the polymer in coordination bonding with the metal was proved by IR spectroscopy. The affinity of chitosan for iron ions was enhanced by introducing phenolic fragments into the polymer.  相似文献   
66.
A method for calculating the distribution of excited electrons in the conduction band of semiconductors has been proposed. This method takes into account both the excitation of electrons by means of an external light source and the transitions to the bottom of the conduction band due to the electron-phonon interaction. The interaction of electrons with the light field has been calculated from first principles in the dipole approximation using the linear muffin-tin orbital method. The electron-phonon interaction has been calculated in terms of the density functional perturbation theory. The method has been applied to the calculation of the quasi-steady-state distribution function of excited electrons in anatase doped with boron, nitrogen, and carbon. The correlations of the distribution function with the photocatalytic activity of doped anatase have been discussed.  相似文献   
67.
The low-frequency dielectric tensor is calculated for AIIBIVC 2 V and AIBIIIC 2 VI crystals in terms of the long-wave frequencies of lattice vibrations, corresponding to various orientations of the wave vector. The qualitative shape of the spectrum of mechanical polaritons is obtained. The coefficient of light reflection is calculated as a function of the frequency and direction of propagation for a CdGeP2 crystal.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 6, pp. 39–43, June, 1978.  相似文献   
68.
A regularity is found for the anomalous behavior of the rotational and centrifugal distortion parameters of the water molecule in the bending states (0v20). This regularity is described by simple nonpolynomial formulae which are used to calculate Watson's parameters A, ΔK, ΔKJ, δK, HK, HKJ, hK, LK, LKKJ, and lK for the states (010), (020), (030), and (040). The calculated v2 behavior of these parameters is in agreement with the experimental one.  相似文献   
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The vibrational representation is decomposed into irreducible representations in the symmetry points of the Brillouin zone. The selection rules are found for a one-phonon IR absorption and Raman scattering of light. In the IR absorption, 17 frequencies are active with polarization along the second-order axis and 16 frequencies are active with a perpendicular polarization. There are 36 frequencies active in the Raman scattering. The basis vectors of the normal vibrations are found for symmetry points of the Brillouin zone and the nature of the long-wave vibrations is investigated. The decomposition of the direct product of irreducible representations is found (selection rules).Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 5, pp. 75–78, May, 1976.The authors thank G. F. Karavaev and N. V. Kudryavtsev for consultations.  相似文献   
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