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1.
The laser-induced fluorescence (LIF) spectrum of jet-cooled 48TiF has been obtained in the wavelength region of 245-270 nm for the first time. Six pairs of vibronic bands were observed and assigned to two new transitions [37.8]4Φ-X4Φ and 4Δ-X4Φ. Rotational analysis was carried out for the (ν′ = 0-3 to ν″ = 0) vibrational bands of the [37.8]4Φ3/2-X4Φ3/2 and [37.8]4Φ5/2-X4Φ5/2 subbands, and also, the (ν′, 0) and (ν′+1, 0) vibrational bands of the 4Δ1/2-X4Φ3/2 and 4Δ3/2-X4Φ5/2 subbands. The effective equilibrium molecular constants for the [37.8]4Φ3/2 and [37.8]4Φ3/2 upper states were determined. In addition, lifetime measurements were carried out for all of the observed bands under collision-free conditions. On the basis of the spectroscopic constants and lifetime measurements, the electronic transitions involved in the observed high-lying electronic states are discussed.  相似文献   

2.
The visible electronic spectrum of AuO has been recorded at rotational resolution using intracavity laser absorption spectroscopy. Five vibrational bands have been analyzed and assigned as the (0, 0), (1, 0), (2, 0), (3, 0), and (4, 0) bands of the b4Π3/2-X2Π3/2 transition of AuO. The molecular parameters for the newly identified b4Π3/2 state are presented.  相似文献   

3.
Emission spectra of WO have been observed in the 4000-35 000 cm−1 region using a Fourier transform spectrometer. Molecules were produced by exciting a mixture of WCl6 vapor and He in a microwave discharge lamp. A 3Σ state has been assigned as the ground state of WO based on a rotational analysis of the observed bands and ab initio calculations. After rotational analysis, a majority of strong bands have been classified into three groups. Most of the transitions belonging to the first group have an Ω = 0+ state as the lower state while the bands in the second group have an Ω′′ = 1 state as the lower state. These two lower states have been assigned as X0+ and X1 spin components of the X3Σ ground state of WO. The third group consists of additional bands interconnected by common vibrational levels involving some very low-lying states. The spectroscopic properties of the low-lying electronic states have been predicted from ab initio calculations. The details of the rotational analysis are presented and an attempt has been made to explain the experimental observations in the light of the ab initio results.  相似文献   

4.
The emission spectrum of NbN has been reinvestigated in the 8000-35 000  cm−1 region using a Fourier transform spectrometer and two groups of new bands were observed. The bands observed in the 18 000-20 000 cm−1 region have been assigned to a new 3Π-X3Δ transition. Three bands with R heads near 19 463.8, 19 659.0 and 19 757.0 cm−1 have been assigned as 0-0 bands of the 3Π2-X3Δ3, 3Π1-X3Δ2 and 3Π-X3Δ1 subbands, respectively, of this new transition. Three additional ΔΩ = 0 bands have been observed in the 24 000-26 000  cm−1 region. A 0-0 band with an R head near 25 409.9 cm−1 has been assigned as a ΔΩ = 0 transition having X3Δ2 as its lower state while two additional bands with heads near 25 518.7 and 25 534.8 cm−1 were found to be ΔΩ = 0 bands having X3Δ1 as the common lower state. Two of these three bands are perhaps subbands of a 3Δ-X3Δ transition. Most of the excited levels are affected by perturbations.  相似文献   

5.
The absorption spectrum of the 18O3 isotopologue of ozone has been recorded in the 6200-6400 cm−1 region by high sensitivity CW-Cavity Ring Down Spectroscopy. The spectrum is dominated by the 2ν1 + 5ν3 and 2ν1 + 3ν2 + 3ν3 bands at 6270.6 and 6392.2 cm−1, respectively which were treated independently. The rovibrational analysis of the 2ν1 + 5ν3 band has evidenced that the (2 0 5) upper state is perturbed by Coriolis resonance interactions with the (0 1 6), (3 0 4) and (3 5 0) states. A total of 659, 89, 131 and 5 transitions were assigned to the 2ν1 + 5ν3, ν2 + 6ν3, 3ν1 + 4ν3 and 3ν1 + 5ν2 bands, respectively. In the case of the 2ν1 + 3ν2 + 3ν3 band, 344 transitions were assigned. Some of them were found perturbed by a Coriolis interaction of the (2 3 3) state with the (5 2 0) state.Overall, 681 energy levels were derived from the analysis of the 2ν1 + 5ν3 and 2ν1 + 3ν2 + 3ν3 band systems. In both cases, a suitable effective Hamiltonian was elaborated, allowing accounting satisfactorily for the retrieved rovibrational energy levels. In addition, dipole transition moment parameters were determined by a least-squares fit to the measured line intensities. The effective Hamiltonian and transition moment operator parameters were used to generate a list of 1619 transitions given as Supplementary material.  相似文献   

6.
The emission spectrum of NbCl has been recorded in the 3000-20 000 cm−1 region using a Fourier transform spectrometer. The bands were observed by microwave excitation of a mixture of NbCl5 vapor and He. Two groups of bands observed in the 6500-7000 cm−1 and 9800-11 000 cm−1 regions have been assigned to two electronic transitions. Five bands observed in the 6500-7000 cm−1 region consist of R, P, and Q branches with no combination defect or Λ-doubling. They have been assigned as five sub-bands of a ΔΛ=±1 transition with Λ>1. Nine bands observed in the 9800-11 000 cm−1 regions consist of R and P branches, and they are also free from Λ-doubling. These bands have been classified into four sub-bands of a ΔΛ=0 transition (with Λ>1), which has tentatively been assigned as . The two transitions have no electronic states in common. Ab initio calculations have been performed on NbCl and the spectroscopic properties of the low-lying electronic states have been calculated. The ground state of NbCl has been predicted to be a state arising from the 3σ1 1δ2 2π1 configuration, with a low-lying state at 1300 cm−1 from the 3σ1 1δ1 2π2 configuration. The results of our experimental and theoretical studies will be presented. This work represents the first experimental investigation of the spectra of NbCl and the first ab initio prediction of the spectroscopic properties of the low-lying electronic states.  相似文献   

7.
The absorption spectrum of the 16O3 isotopologue of ozone has been recorded in the 7000-7920 cm−1 region by high sensitivity CW-Cavity Ring Down Spectroscopy. This report is devoted to the analyses of the 7065-7300 cm−1 region dominated by the ν1 + 2ν2 + 5ν3 and ν1 + 5ν2 + 3ν3 A-type bands at 7130.8 and 7286.8 cm−1 respectively. 289 transitions were assigned to the ν1 + 2ν2 + 5ν3 band. The corresponding line positions were modeled with an effective Hamiltonian involving Coriolis resonance interactions between the (1 2 5) upper state and the (4 4 0), (0 2 6) and (6 1 0) dark states, and an anharmonic resonance interaction with the (2 0 5) state. The very strong interaction (up to 50% mixing of the wavefunctions) between the (1 2 5) and (6 1 0) states leads to the observation of two extra lines of the 6ν1 + ν2 band due to a resonance intensity transfer. 213 transitions of the ν1 + 5ν2 + 3ν3 band were assigned and modeled taking into account a Coriolis resonance interaction with the (3 6 0) state.We take the opportunity of the present work to report the analysis of the very weak 4ν2 + 4ν3 B-type band at 6506.1 cm−1 which was assigned from previously recorded CRDS spectra. 286 transitions were modeled using the effective Hamiltonian approach.The dipole transition moment parameters of the three analyzed bands were determined by a least-squares fit to the measured line intensities. For the three 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   

8.
New high resolution emission spectra of CoH and CoD molecules have been recorded in the 640 nm to 3.5 μm region using a Fourier transform spectrometer. The bands were excited in a carbon tube furnace by the reaction of cobalt metal vapor and a mixture of H2 or D2 with He at a temperature of about 2600 °C. Eight bands were observed for the A3Φ4-X3Φ4 electronic transition of CoD, and five bands for the corresponding transition of CoH. The (0, 0) bands of the A3Φ3-X3Φ3 system were also recorded for both isotopologues, although one of the parity components in the X3Φ3 sub-state of CoH was found to be perturbed. The A3Φ3-X3Φ4 transition was also observed in our spectrum of CoH. In addition, a new [13.3]4 electronic state was found by observing [13.3]4-X3Φ3 and [13.3]4-X3Φ4 transitions in the spectrum of CoD. Analysis of the transitions with ΔΩ = 0, ± 1 provided more accurate values of spin-orbit splittings between Ω = 4 and Ω = 3 components. The ground-state data for both molecules were fitted both to band-constant and Dunham-expansion expressions, and a combined-isotopologue analysis of the X3Φ4 spin component was carried out using the data for CoH and CoD. The upper states were represented by term values in these analyses because of perturbations, but estimated band constants for them were obtained in separate fits in which ground-state constants were held fixed.  相似文献   

9.
High-resolution spectra of VO have been reinvestigated in the 12 000-31 000 cm−1 region. VO was produced in a vanadium hollow cathode lamp by discharging 1.5 Torr of Ar and the spectra were recorded using a Fourier transform spectrometer. The oxygen needed to produce VO was present in the system as an impurity. Three new bands observed in the 21 000-22 100 cm−1 region have been attributed to a new 2Δ-12Δ electronic transition of VO. Two bands, with origins near 21 044 and 22 038 cm−1, have been assigned as the 0-1 and 0-0 bands of the 2Δ3/2-12Δ3/2 sub-band while a weak band with an origin near 21 975 cm−1 has been assigned as the 0-0 band of the corresponding 2Δ5/2-12Δ5/2 sub-band. A rotational analysis of these sub-bands has been obtained and spectroscopic constants have been extracted. The 12Δ state is known from the previous analyses of the doublet transitions of VO in the near infrared. The present observation has allowed the determination of the vibrational interval ΔG1/2 and the equilibrium rotational constants for the 12Δ3/2 state.  相似文献   

10.
Rhodium monochloride has been observed and characterized spectroscopically for the first time. The RhCl molecules were produced in a laser vaporization molecular beam source by the reaction of a laser vaporized rhodium plasma with CCl4 doped in helium, and laser-induced fluorescence and dispersed fluorescence were used to study 15 of the strongest bands spanning the 535-415 nm region. Twelve of these bands were studied at high resolution using a cw ring dye laser. Two low-lying states separated by 140 cm−1 have been observed. The ground state has Ω = 2 and is attributed to a 3Πi state resulting from a δ4π3σ1 electronic configuration. The other low-lying state has Ω = 3 and is attributed to a 3Δi state resulting from a δ3π4σ1 electronic configuration. Excited states with Ω values ranging from 1 to 4 have been observed. Dispersed fluorescence from these excited levels has been used to identify a large number of low-lying electronic states within an energy range of 5200 cm−1 and has also been used to determine a ground state vibrational frequency of ∼348 cm−1. Λ-doublings have been observed in all the transitions studied at high resolution.  相似文献   

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