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1.
Shaohua Zhang 《Journal of Molecular Spectroscopy》2008,252(1):77-80
The laser-induced fluorescence excitation spectra of jet-cooled CuS molecules have been recorded in the energy range of 17 200-19 500 cm−1. Fourteen observed vibronic bands have been assigned as three transition progressions: A2Σ− (v′ = 0-4)-X2Π3/2 (v″ = 0), A2Σ− (v′ = 0-4)-X2Π3/2 (v″ = 1), and A2Σ− (v′ = 0-3)-X2Π1/2 (v″ = 0). Spectroscopic constants of both the X2Π ground state and the A2Σ− excited state of 63CuS and 65CuS were determined by analyzing their rotationally resolved spectra. Furthermore, the lifetimes of most observed bands were measured for the first time. 相似文献
2.
A combined analysis of the A2Πi → X2Σ+ and B2Σ+ → X2Σ+ band systems of AlO, involving 21,500 line assignments, has been performed. The analysis indicates that the previously reported γ values of the B2Σ+ state are questionable. The present analysis shows that γ(B2Σ+) ≈ 0.014 cm−1, essentially independent of the vibrational level. The positive sign is consistent with second order interaction with the higher-lying C2Πr and lower-lying A2Πi states. It also appears that many of the previously reported γ and γD values of X2Σ+ (v > 0) are doubtful. In fact, γ(X2Σ+) is observed to become increasingly negative for v″ > 1, due to second order interaction with the low-lying A2Πi state. The present results are based on models where the hyperfine structure of the 2Σ+ states has been taken into account explicitly. Intensity patterns of the branches of the B2Σ+ → X2Σ+ system have been shown to be influenced by the case bβS coupling in the ground state v = 0,1 levels. This gives rise to intensity differences of around 10 percent in the R1/R2 and P1/P2 doublet components. The synthesized intensity patterns are fully in accord with the F1/F2 assignments of the present work. 相似文献
3.
Randall H. Skelton Chris D. Boone Peter F. Bernath Bernard Pinchemel 《Journal of Molecular Spectroscopy》2003,219(1):1-12
The A′1Π-X1Σ+ near infrared system of strontium oxide (SrO) was observed at high spectral resolution by measuring the chemiluminescence from a Broida flow reactor using a Fourier transform spectrometer. In total, 32 bands from , , were measured within the spectral region at a resolution of . Vibrational levels of the upper state were observed up to vA′=4, and more than 5600 rotational lines were assigned. Incorporating previously published high resolution data for the A1Σ+-X1Σ+ system, a global fit to both data sets yields improved Dunham constants for the ground state and for the lower vibrational levels (vA′=0, 1, and 2) of the A′1Π state. Because perturbations arising from interactions with the b3Σ+ and A1Σ+ states affect the higher vibrational levels of the A′1Π state more strongly, levels vA′=3 and 4 were represented by effective band constants in the fits. RKR potentials for the X1Σ+,A′1Π, and b3Σ+ states have been generated utilizing all the available data, Franck-Condon factors have been calculated for the A′1Π-X1Σ+ system, and A′1Π∼b3Σ+ and A′1Π∼A1Σ+ perturbations are discussed. 相似文献
4.
Christopher R. Brazier José I. Ruiz Sylvia V. Parks 《Journal of Molecular Spectroscopy》2007,241(1):1-6
The gas phase spectrum of the silicon boride radical has been observed for the first time. Two electronic transitions were observed in emission from a corona excited supersonic expansion source. The D4Σ−-X4Σ− system consists of emission from v′ = 0 to v″ = 0-3, while the A4Π-X4Σ− system consists of numerous bands with v′ = 0-5 and v″ = 0-11, although only the strong 0-0 and 0-1 bands have been analyzed so far. 相似文献
5.
K.D. Setzer 《Journal of Molecular Spectroscopy》2006,236(2):224-233
Emission spectra of the b1Σ+(b0+) → X3Σ−(X10+,X21) and a1Δ(a2) → X21 transitions of AsBr have been measured in the near-infrared spectral region with a Fourier-transform spectrometer. The arsenic bromide radicals were generated in fast-flow systems by reaction of arsenic vapor (Asx) with bromine and were excited by microwave-discharged oxygen. The most prominent features in the spectrum are the Δv = +1,0,−1, and −2 band sequences of the b1Σ+(b0+) → X3Σ−(X10+) transition in the range 11 700-12 700 cm−1. With lower intensities, the Δv = 0 and −1 sequences of the b1Σ+(b0+) → X3Σ−(X21) sub-system show up in the same range. Further to the red, between 6000 and 6700 cm−1, the Δv = 0, +1, and −1 sequences of the hitherto unknown a1Δ(a2) → X21 transition are observed. Analyses of medium- and high-resolution spectra have yielded improved molecular constants for the X10+, X21, and b0+ states and first values of the electronic energy and the vibrational constants of the a2 state. 相似文献
6.
Shanshan Yu 《Journal of Molecular Spectroscopy》2005,230(2):105-116
The vibration-rotation emission spectra for the X2Π ground state and the near infrared emission spectra of the X2Π1/2-X2Π3/2 system of the TeH and TeD free radicals have been measured at high resolution using a Fourier transform spectrometer. TeH and TeD were generated in a tube furnace with a DC discharge of a flowing mixture of argon, hydrogen (or deuterium), and tellurium vapor. In the infrared region, for the X2Π3/2 spin component we observed the 1-0, 2-1, and 3-2 vibrational bands for most of the eight isotopologues of TeH and the 1-0 and 2-1 bands for three isotopologues of TeD. For the X2Π1/2-X2Π3/2 transition, we observed the 0-0 and 1-1 bands for TeH and the 0-0, 1-1, and 2-2 bands for TeD. Except for a few lines, the tellurium isotopic shift was not resolved for the X2Π1/2-X2Π3/2 transitions of TeH and TeD. Local perturbations with Δv = 2 between the two spin components of the X2Π state of TeH were found: X2Π1/2, v = 0 with X2Π3/2, v = 2; X2Π1/2, v = 1 with X2Π3/2, v = 3. The new data were combined with the previous data from the literature and two kinds of fits (Hund’s case (a) and Hund’s case (c)) were carried out for each of the 10 observed isotopologues: 130TeD, 128TeD, 126TeD, 130TeH, 128TeH, 126TeH, 125TeH, 124TeH, 123TeH, and 122TeH. 相似文献
7.
Ching-Ping Liu Colin M. Western Yuan-Pern Lee Reginald Colin 《Journal of Molecular Spectroscopy》2006,238(2):213-223
Spectra of the B3Σ−- X3Σ− transition in SO above the first dissociation limit are recorded using degenerate four wave mixing. These spectra are combined with earlier work involving laser induced fluorescence, absorption spectra and Fourier transform emission spectra, to enable a rotational analysis and deperturbation of vibrational levels of the B state up to v′ = 16. Numerous perturbations were noted within the B3Σ− state, and the origin of these is discussed. In a number of cases, these perturbations can be attributed to interactions with specific other electronic states of SO, such as A3Π, C3Π, d1Π, and A″ 3Σ+. 相似文献
8.
Six bands in the 0-v″ progression and three bands in the 1-v″ progression of the A2Πi → X2Πr visible system of SO+ have been recorded photoelectrically and rotationally assigned. Molecular constants for v′ = 0 and 1 in the A state and for v″ = 4–9 in the X state have been obtained using direct fitting and merging techniques. 相似文献
9.
《Journal of Molecular Spectroscopy》1987,122(2):417-427
A new method of producing strong and clean emission spectra of the gallium hydride/deuteride molecule has been developed. Five bands belonging to the gallium deuteride molecule (GaD) have been photographed under high resolution. The rotational analyses of the bands lying at 5669.14 Å (0-0) and 5675.10 Å (1-1) in the a3Π1-X1Σ+ transition, 5761.0 Å (0-0) and 5766.20 Å (1-1) in the a3Π0+-X1Σ+ transition, and 5760.85 Å (0-0) in the a3Π0−-X1Σ+ transition have been performed. Accurate rotational constants (B, D) have been determined for the X1Σ+, a3Π0± and a3Π1± states. The Λ doubling in the a3Π0 (v = 0) and a3Π1 (v = 0 and 1) states are obtained. 相似文献
10.
Iouli E. Gordon Alireza Shayesteh Peter F. Bernath 《Journal of Molecular Spectroscopy》2005,229(1):145-149
Fourier transform infrared emission spectra of MnH and MnD were observed in the ground X7Σ+ electronic state. The vibration-rotation bands from v = 1 → 0 to v = 3 → 2 for MnH and from v = 1 → 0 to v = 4 → 3 for MnD were recorded at an instrumental resolution of 0.0085 cm−1. Spectroscopic constants were determined for each vibrational level and equilibrium constants were found from a Dunham-type fit. The equilibrium vibrational constant (ωe) for MnH was found to be 1546.84518(65) cm−1, the equilibrium rotational constant (Be) is 5.6856789(103) cm−1 and the eqilibrium bond distance (re) was determined to be 1.7308601(47) Å. 相似文献
11.
Near-infrared emission spectra of the X22Π3/2 → X12Π1/2 fine structure transitions of PbH and PbD have been investigated by high-resolution Fourier-transform spectrometry. The fine structure splitting in the X2Πr ground state of 208PbH was found to be 6924.4926(4) cm−1. Accurate rotational constants for the v = 0 and 1 vibrational levels of the X2Πr states of 208PbH, 207PbH, 208PbD and 207PbD and hyperfine structure constants for the X12Π1/2 states of 207PbH (207PbD) have been derived. 相似文献
12.
The emission spectra of the A2П-X2Σ+ (red) system of 12C14N have been reinvestigated in the 3500-22 000 cm−1 region at high resolution using a Fourier transform spectrometer. In total, spectra of 63 bands involving vibrational levels up to v′ = 22 of the A2П state and v″ = 12 of the X2Σ+ ground state have been measured and rotationally analyzed providing an improved set of spectroscopic constants. The present measurements of the Δv = −2 sequence bands of 12C14N and those of 13C14N from Ram et al. (2010) [36] allow for a much improved identification of these two isotopologues in the near infrared spectra of carbon stars. 相似文献
13.
K.D. Setzer 《Journal of Molecular Spectroscopy》2003,221(1):19-22
Emission spectra of the b1Σ+(b0+)→X3Σ−(X10+) transition of phosphorus iodide have been measured with a high-resolution Fourier-transform spectrometer. The PI radicals were generated and excited in a fast-flow system by reaction of phosphorus vapor (Px) with iodine and microwave-discharged oxygen. Four sequences, Δv=0,+1,−1,−2, of the b1Σ+(b0+)→X3Σ−(X10+) transition of PI comprising 28 bands were observed. Six bands were measured at high spectral resolution. Vibrational and rotational analyses have yielded accurate spectroscopic constants of the X10+ and b0+ states (in cm−1): X10+: ωe=371.296(4), ωexe=1.3302(9), Be=0.1194117(2), αB=−0.0005676(7), De=4.56(2) ×10−8; b0+: Te=11136.921(4), ωe=400.165(6), ωexe=1.345(2), Be=0.1239237(2), αB=−0.0005540(2), De=4.84(5) × 10−8, where the numbers in parentheses are the standard deviations of the parameters. No emissions of the b0+→X21 sub-system nor of the a1Δ(a2)→X3Σ−(X21) transition have been observed leaving PI the only group Va halide for which the spin splitting in the X3Σ− ground state is still unknown. 相似文献
14.
Rotational spectra have been observed for BiO produced in a DC discharge through a low pressure mixture of O2, Ar, and Bi vapor. Because of the highly non-thermal distribution of states, it has been possible to observe spectra arising from the X12Π1/2 level up to v = 9 and for the X22Π3/2 level up to v = 5 near 10 538 cm−1. Precise rotational and hyperfine parameters have been determined for the observed states. By using available near infrared (NIR) data in a merged fit, the 0-0 and 1-1 fine structure intervals have been more precisely determined. Although the quality of the fit is very good, the interpretation of the hyperfine constants is complicated by relativistic effects and the interaction of the X2 state with A14Π3/2 state. The magnetic and quadrupole coupling constants will be compared with those of the Bi atom and related molecules. 相似文献
15.
High resolution emission spectra of ScF molecule have been observed in the region of 21 120-21 300 cm−1 and of 15 640-15 710 cm−1. The rotational structures in 4-2 band of D1Π-X1Σ+ and in 4-4 band of D1Π-A1Δ were assigned. Rotational analysis reveals the presence of localized perturbations in the upper state D1Π v = 4 level at different values of J for the two parity sublevels, e and f. These perturbations are interpreted as the consequence of a spin-orbit interaction between D1Π state and a triplet state of 3Π symmetry. A matrix model describing the energies within the two interacting levels, has been used to fit term-values. Spectroscopic constants are obtained for A1Δ v = 4, D1Π v = 4 and for the 3Π perturbing level. The magnitude of the spin-orbit interaction is estimated. 相似文献
16.
The electronic emission spectrum of the A3Π0-X1Σ+ and B3Π1-X1Σ+ transitions of Gallium monochloride molecule (69GaCl) has been recorded on BOMEM DA8 Fourier transform spectrometer at an apodized resolution of 0.035 cm−1. The rotational structure of the 0-0, 1-0, 2-1, and 3-2, bands belonging to A-X and 0-0, 0-1, 1-2, and 0-2 bands belonging to B-X transitions has been analyzed and equilibrium rotational constants for the X1Σ+ and A3Π0 states have been obtained. For the first time we are able to determine the Λ-doubling constants in the v = 0 and 1 levels of the B3Π1 state. 相似文献
17.
High resolution infrared emission spectra of ZnH, ZnD, CdH, and CdD have been recorded with a Fourier transform spectrometer. The v = 1 → 0 and v = 2 → 1 bands of ZnH, ZnD, CdH, and CdD, as well as the v = 3 → 2 band of ZnD were observed for the X2Σ+ ground electronic state. In addition, new rotational spectra have been recorded for CdH and CdD using a tunable far-infrared spectrometer, and pure rotational transitions in the v = 1 level of the ground state were measured. The new data were combined with the previous data from diode laser infrared spectra and pure rotation spectra of ZnH/ZnD and CdH/CdD available in the literature. The data from all isotopologues were fitted together using a Dunham-type energy level expression for 2Σ+ states, and Born-Oppenheimer breakdown correction parameters were obtained. The equilibrium rotational constants (Be) of 64ZnH, 64ZnD, 114CdH, and 114CdD were determined to be 6.691332(17), 3.402156(7), 5.447074(18), and 2.750761(6) cm−1, respectively, and the associated equilibrium internuclear distances (re) are 1.593478(2), 1.593001(2), 1.760098(3), and 1.759695(2) Å, respectively. Simple reduced mass scaling for the spin-rotation interaction constants of ZnH and CdH fully accounted for their isotopologue dependence, and no Born-Oppenheimer breakdown correction was required for these parameters. 相似文献
18.
R. PereiraS. Skowronek A.González Ureña A. PardoJ.M.L. Poyato A.H. Pardo 《Journal of Molecular Spectroscopy》2002,212(1):17-21
Rotationally resolved spectra of the CaH radical using a supersonic molecular beam are reported. Thus, high energy resolution of the (1+1′) REMPI spectra corresponding to the A←X and B←X electronic transitions were measured which allowed for the first time a clear and precise analysis of the low rotational part (J≤7) of the CaH spectrum. A comparison with previous studies revealed that the commonly accepted energy separation between the two band heads of B−X (v′=1, v′=0) of 10 cm−1 is not correct. A value of ca. 1.6 cm−1 was found to be more realistic. On the other hand, the present study confirmed that the perturbation appears only for v′=1, N′>3 of the B state. 相似文献
19.
L.N. Zack 《Journal of Molecular Spectroscopy》2009,256(2):186-236
The pure rotational spectrum of ZnO has been measured in its ground X1Σ+ and excited a3Πi states using direct-absorption methods in the frequency range 239-514 GHz. This molecule was synthesized by reacting zinc vapor, generated in a Broida-type oven, with N2O under DC discharge conditions. In the X1Σ+ state, five to eight rotational transitions were recorded for each of the five isotopologues of this species (64ZnO, 66ZnO, 67ZnO, 68ZnO, and 70ZnO) in the ground and several vibrational states (v = 1-4). Transitions for three isotopologues (64ZnO, 66ZnO, and 68ZnO) were measured in the a3Πi state for the v = 0 level, as well as from the v = 1 state of the main isotopologue. All three spin-orbit components were observed in the a3Πi state, each exhibiting splittings due to lambda-doubling. Rotational constants were determined for the X1Σ+ state of zinc oxide. The a3Πi state data were fit with a Hund’s case (a) Hamiltonian, and rotational, spin-orbit, spin-spin, and lambda-doubling constants were established. Equilibrium parameters were also determined for both states. The equilibrium bond length determined for ZnO in the X1Σ+ state is 1.7047 Å, and it increases to 1.8436 Å for the a excited state, consistent with a change from a π4 to a π3σ1 configuration. The estimated vibrational constants of ωe ∼ 738 and 562 cm−1 for the ground and a state agreed well with prior theoretical and experimental investigations; however, the estimated dissociation energy of 2.02 eV for the a3Πi state is significantly higher than previous predictions. The lambda-doubling constants suggest a low-lying 3Σ state. 相似文献
20.
The B3Π(0+) ← X1Σ+ absorption spectrum of BrF (4850–5200 Å) has been observed by the technique of laser emission spectroscopy. Fluorescence was excited by a pulsed, scannable dye laser with a 0.1 Å bandwidth. Rotational analysis has been carried out for six bands of the v″ = 0 progression (8 ≥ v′ ≥ 3) of 79BrF and 81BrF. Rotational constants for the B3Π(0+) state are reported for the first time. RKR potential energy curves for both states, and an array of Franck-Condon factors and r-centroids for the transition, have been calculated. Bands with v′ > 8 were not observed in fluorescence owing to the onset of predissociation near J′ = 28 of the v′ = 8 level. An upper limit for the ground state dissociation energy is D0″ (BrF, X1Σ+) ≤ 20 880 cm?1. 相似文献