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1.
The vibration-rotation transitions for v = 1 ← 0 of NO () have been studied by using the technique of laser magnetic resonance spectroscopy. Five magnetic resonance lines are observed with three CO laser lines in the range from 1859 to 1886 cm?1. From these, three zero-field transition frequencies, v = 1 ← 0; , , and are obtained with an accuracy of ±0.0007 cm?1. The molecular constants which have been determined by borrowing centrifugal constants from a previous infrared work are , , and . 相似文献
2.
The rotational structure of the 2B1 (K′ = 0) subbands of NO2 with v′2 = 6, 7, 8, and 9 were analyzed by means of the time-gated excitation spectrum. The excitation spectrum monitored at ν2, 2ν2, or 3ν2 fluorescence band was fairly simplified in comparison to its corresponding absorption spectrum. The band origins and rotational constants are evaluated from the observed data: ν0 = 20205.0 cm?1, for v′2 = 6; ν0 = 21104.4 cm?1, for v′2 = 7; ν0 = 22001.9 cm?1, for v′2 = 8ν0 = 22898.0 cm?1, for v′2 = 9. The value of extrapolated to v′ = 0 is 0.370 cm?1. This value corresponds to the bond length of 1.19 Å. Fluorescence decays of these excited levels were also studied. Radiative lifetimes obtained by extrapolation to zero pressure from the plots were 25–40 μsec. The short-lived excited levels previously reported by some authors were not found. 相似文献
3.
A weak emission spectrum of I2 near 2770 Å is reanalyzed and found to to minate on the A(1u3Π) state. The assigned bands span v″ levels 5–19 and v′ levels 0–8. The new assignment is corroborated by isotope shifts, band profile simulations, and Franck-Condon calculations. The excited state is an ion-pair state, probably the 1g state which tends toward . In combination with other results for the A state, the analysis yields the following spectroscopic constants: T″e = 10 907 cm?1, ″e = 1640 cm?1, ω″e = 95 cm?1, ; T′e = 47 559.1 cm?1, ω′e = 106.60 cm?1, . 相似文献
4.
Peter J Domaille Timothy C Steimle David O Harris 《Journal of Molecular Spectroscopy》1977,68(1):146-155
The pure rotational spectrum of the state of the gaseous SrF radical has been measured using microwave optical double resonance (MODR) techniques. The analysis fully confirms the recent dye laser excitation spectrum and rotational assignment of the system. Transitions were measured in both the v″ = 0 and v″ = 1 states to give values of Be″ = 0.250533 cm?1, αe″ = 1.546 × 10?3 cm?1 and γ″ (spin-rotation) = 2.49 × 10?3 cm?1. General qualitative features of MODR in 2Σ+ states are treated and suggested improvements for obtaining experimental hyperfine constants are discussed. The more precise ground state constants are merged with the B-X optical analysis to obtain a more accurate set of constants for both states. 相似文献
5.
Single srystals of calcium tartrate doped with VO2+ are grown from silica gel. Its optical absorption spectrum is studied at laboratory and liquid air temperatures. The spectrum is analysed and ascribed to VO2+ ion in C4v symmetry. The following crystal field parameters are evaluated. 相似文献
6.
The infrared spectrum of yttrium monoiodide has been excited in an electrodeless microwave discharge and explored between 2500 and 12 000cm?1 with a high-resolution Fourier transform spectrometer. A unique system is observed (ν00 = 9905.520 cm?1), which we attribute to a transition and an extensive analysis is made. Rovibrational constants are obtained for both states mainly from a simultaneous multiband fitting. This procedure is applied to the whole set of 2231 observed line wavenumbers in the 1-0, 0-0, and 0–1 bands, yielding a final weighted standard deviation of 0.0038 cm?1. Furthermore, a partial analysis of the 2-0 and 3-1 bands is performed. The following equilibrium constants are derived (cm?1): High-order constants Dv and Hv are also calculated for the various vibrational levels (v′ = 0, 1, 2, 3; v″ = 0, 1). 相似文献
7.
L Nemes 《Journal of Molecular Spectroscopy》1978,72(1):102-123
Medium resolution infrared grating spectra of gaseous ketene, H2CCO were recorded between 1000 and 400 cm?1, both at instrument temperature (40°C) and with cooling (?40°C). Interferometric Fourier spectra were also measured at ?70°C with resolution 0.22 cm?1 between 450 and 330 cm?1. The K structure of the fundamentals ν5, ν6, ν8, and ν9 was assigned. These fundamentals are coupled by a-axis Coriolis interactions. These couplings were analysed on the symmetric top basis for setting up the perturbation matrix and by utilizing the K-dependent Coriolis shifts of levels. A preliminary analysis of the Coriolis intensity anomalies was also undertaken.Band center values from combination differences are and . Synthetic spectra indicate the band origins of ν8 and ν9 to be close to 977.8 and 439.0 cm?1, respectively. Estimates of Coriolis coupling constants obtained from synthetic spectra are , , , and . Approximate ratios of unperturbed vibrational transition moments obtained from spectral simulations are . 相似文献
8.
The Raman active fundamentals ν1(A1g), ν2(Eg), ν5(F2g), and the overtone 2ν6 of SF6 have been investigated with a higher resolution and the band origins were estimated to be: ν1 = 774.53 cm?1, ν2 = 643.35 cm?1, ν5 = 523.5 cm?1, and 2ν6 = 693.8 cm?1. Raman and infrared data have been combined for estimation of several anharmonicity constants. The ν6 fundamental frequency is calculated as 347.0 cm?1. From the analysis of the ν2 Raman band, the following rotational constants of both the ground and upper states have been calculated: ; . 相似文献
9.
Kentarou Kawaguchi Chikashi Yamada Yoshiaki Hamada Eizi Hirota 《Journal of Molecular Spectroscopy》1981,86(1):136-142
The fundamental bands of the CF radical in the and electronic states were observed by using an infrared tunable diode laser as a source. Zeeman modulation could be used in detecting lines not only in the state, but also in , because the CF radical deviates considerably from Hund's case (a). From the least-squares analysis of the observed spectra, the following molecular constants were obtained: Be = 1.416 704 (37) cm?1, αe = 0.018 419 (50) cm?1, , De = 6.68 (15) × 10?6cm?1, p0 = 0.008 580 (21) cm?1, p1 = 0.008 52 (11) cm?1, and , with three standard errors in parentheses. 相似文献
10.
Keiji Matsumura Kentarou Kawaguchi Keiichi Nagai Chikashi Yamada Eizi Hirota 《Journal of Molecular Spectroscopy》1980,84(1):68-73
The v = 1 ← 0 vibration-rotation bands of the NS radical in the and electronic states were observed by using a tunable diode laser. From the least-squares analysis the band origins were determined to be 1204.2755(12) and 1204.0892(19) cm?1, respectively, for and . The rotational and centrifugal distortion constants and the internuclear distance in the X2Π electronic state were obtained as follows: Be = 0.775549(10) cm?1, De = 0.00000129(33) cm?1, and , with three standard deviations indicated in parentheses. 相似文献
11.
The (0,0) band of the emission (Infrared Afterglow) system of molecular nitrogen has been recorded with a resolution of 0.046 cm?1 and a line position accuracy of 0.007 cm?1. Six hundred and seventy-two lines are tabulated into a line list for the 1.53 μm (low-resolution) emission feature. Of these, 482 are assigned as members of the 27 branches of the B′ → B transition, while 150 are identified with the 1PG (3,6) band. Molecular constants for the v = 0 levels of the and B3Πg states have been computed and tabulated. 相似文献
12.
We consider the possibility that the scalar partners of the neutrinos are the least massive supersymmetric partners, and show that this alternative is compatible with cosmological constraints, which put a significant lower bound on photino masses but not on masses. Various consequences are examined: the photon counting rate for may be large; the rate for by exchange is enhaced; Z0→ increases Γ(Z0) by about 0.25 GeV; may be enhanced; the decay may be detectable; there can be additional contributions to the rare decay ; restrictions on gluino masses, which depend on photinos interacting before they decay, have to be re-examined; scalar neutrinos have suitable characteristics as candidates for dark matter in the universe. We discuss one currently fashionable class of models that can predicr a light . 相似文献
13.
M.A. Mélières M. Chenevier F. Stoeckel 《Journal of Quantitative Spectroscopy & Radiative Transfer》1985,33(4):337-345
Quantitative measurements of intensities and widths were made for individual rotational lines of the atmospheric oxygen γ band by using a recently developed, highly sensitive, intracavity laser-absorption spectroscopic technique (ICLAS) at 300 torr m. The total band intensity derived from the line intensities is (STP). Self-broadening collision coefficients for the PP and PQ branch lines have been determined from the absorption line width and were found to vary from 0.055 cm?1 atm?1 at N″ = 1 to 0.037 cm?1 atm?1 at N″ = 27. 相似文献
14.
The possibility of neutron triplet pairing and superfluidity in neutron star matter is investigated, and the energy gap and corresponding critical temperature is calculated or estimated as a function of Fermi momentum or density. The calculations are performed for a “one-pion-exchange gaussian” potential, and compared with the results for neutron and proton singlet pairing and superfluidity calculated earlier.The results indicate that neutron superfluidity, corresponding specifically to 3P2 state pairing, may exist in a high-density shell in the nuclear-matter region of a neutron star, i.e. for 1.6 × 1014g/cm3 < ρ < 1.4 × 1015g/cm3, and the maximum self-consistent energy gap is Δ01kF ≈ 0.6 MeV and Δ03(kF) ≈ 0.1 MeV for an effective mass , i.e. for a mas ? ≈ 5.2 × 1014g/cm3. For we get correspondingly Δ01(kF) ≈ 3.3 MeV and Δ03(kF) ≈ 0.6 MeV for kF ≈ 2.2 fm?1. 相似文献
15.
CFCl has been produced for spectral investigation by matrix reactions of alkali metal atomic beams with CFCl3 in argon followed by rapid quenching to 15°K on a tilted copper wedge. When these samples were irradiated with near uv light from a krypton ion laser, a very intense, highly structured fluorescence spectrum was observed. This emission system extended from about 25 000 cm?1 to 15 000 cm?1 and peaked in intensity at about 22 000 cm?1. The three most intense progressions are assigned to transitions from a common excited state to ground state levels (0v20), (1v20) and (1v21). New molecular constants determined from these progressions include , x22 = ?1.2 cm?1, x12 = ?3 cm?1, x23 = ?4 cm?1, and x13 = ?6 cm?1. CFCl was also produced by in situ photolysis of CFCl3 using laser plasma emission and by alkali metal atom reactions with CF2Cl2, CF2ClBr, and CHFCl2. 相似文献
16.
Optically detected magnetic resonance has been used to investigate exciton recombination in the layered semiconductor GaS. Five triplet exciton resonances have been observed all with the same g-value of gex6 = 2.006 ± 0.002 but with different zero field splittings: , . The resonances from the high energy wing are remarkably narrow and we believe that this may be the first observation of resonance from free indirect excitons. 相似文献
17.
The Raman Spectra of carbon-deficient sputtered amorphous SiC films contain an intense band centered at 1442 cm?1. This band is attributed to the presence of C-C bonds. Similarly a peak at ~508 cm?1 is attributed to Si-Si bonds. The depolarization spectrum was found to be constant at for . Our results indicate a degree of compositional disorder which prevents an identification of the observed like-atom bonds with those predicted by a modified Polk model. 相似文献
18.
H.D. Bist J.C.D. Brand A.R. Hoy V.T. Jones R.J. Pirkle 《Journal of Molecular Spectroscopy》1977,66(3):411-420
The band system of NO2, , has been measured in absorption in a neon matrix at 6 K, using 15NO2 and N18O2 in addition to the normal isotope. The spectrum consists essentially of a single, long progression of bands terminating on successive levels of the bending mode in the upper state. Transitions to odd- and even-v2′ states occur with a uniform intensity distribution indicating that the rotation of the bent ground state of NO2 about its near-prolate axis is hindered in the matrix. The observations strongly suggest that the top axis of the molecule coincides with a C2 axis of neon crystals in the polycrystalline matrix. Relative to the vapor absorption the matrix spectrum is red shifted by about 150 cm?1, the crystal field parameter V2 and principal constants of the state of 14N16O2 in neon being 相似文献
19.
Rotationally resolved infrared-ultraviolet double resonance (IRUVDR), consisting of sequentially excited rovibrational and rovibronic transitions sharing a common intermediate molecular level, is demonstrated. The technique employs pulsed CO2 and tunable dye lasers and is applied to the molecules D2CO and HDCO. For D2CO, infrared pumping produces 100fold population enhancement in specific rotational sublevels of the v4 = 1 level of the electronic ground state, followed by ultraviolet excitation in the 365-nm 410 band of the electronic system. This ultraviolet excitation occurs at a specific set of dye laser frequencies, determined by the preceding rovibrational transition, and is detected by molecular fluorescence in the visible region. Similar effects observed in HDCO involve rovibrational pumping to either the v6 = 1 or v5 = 1 levels and give rise to enhanced rovibronic transitions in the 610 and 510 bands of the system, respectively. The resulting IRUVDR spectra enable detailed spectroscopic assignments to be made and are consistent with previous results from infrared and ultraviolet absorption, laser Stark, and infrared-radiofrequency double resonance spectroscopy. Collision-induced satellite structure, arising from rotational relaxation of the intermediate rovibrational level in the IRUVDR sequence, is also reported. 相似文献
20.
We discuss quantitatively the production of charm in neutral current interactions, and the anomalous lepton events that follow from semi-leptonic charm decay. Diagonal neutral currents, in the Weinberg-Salam model and similar models, predict associated charm production with small cross sections: e.g. at high energy. The meagre data on vN → ve+X are consistent with a rate of this order. Non-diagonal neutral currents, if present, could give larger cross sections via valence p → c transitions. It should be possible to distinguish diagonal from non-diagonal contributions by their x- or u-dependences, where u = x(1 ? y). We calculate the expected energy distributions of the leptons in characteristic vN → v?+X and vN → v?+??X charm decay events using simple models, and discuss some practical problems in neutral current measurements. 相似文献