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1.
Doppler-limited laser excitation spectroscopy employing narrow-band fluorescence detection was used to obtain a rotational and vibrational analysis in the (0, 0) and (1, 1) bands of the A2Π-X2Σ+ system and the (4, 2) (3, 1), (0, 0), (0, 1), (1, 2), (2, 3), and (3, 4) bands of the B2Σ+-X2Σ+ system of CaI. The A and B states are deperturbed to obtain spectroscopic constants and Franck-Condon factors. Deperturbation was necessary because of the small separation of the A and B states relative to the AB interaction strength and the A2Π spin-orbit splitting. The main deperturbed constants (in cm?1) are
  相似文献   

2.
Laser excitation spectra have been recorded for Ca79Br and Ca81Br in the spectral region 600–630 nm. The use of a 1-m monochromator as a narrow band pass filter (1–2 cm?1) has allowed rotational analysis of the 0-0, 1-1, and 2-2 bands of the B2Σ+ - X2Σ+ transition and the 0-0 and 1-1 bands of the A2Π - X2Σ+ transition. A few additional lines of the 0-1, 1-2, 1-0, and 2-1 bands of the B-X system were used to obtain band origins for vibrational analysis. The main constants for Ca79Br are (in cm?1):
X2Σ+A2ΠB2Σ+
Te015 624.67(5)15 700.52(12)
ωe238.7496(33)241.19(7)242.63(17)
ωeχe0.62789(64)0.53(5) (Pekeris)1.17(12) (Pekeris)
Be0.0693254(84)0.070460(14)0.071572(22)
αe × 1042.640(35)2.15(10)3.95(2)
Ae45.8968(52)
Re(A?)2.8286(2)2.8057(3)2.7839(4)
  相似文献   

3.
Sub-Doppler optical-optical double-resonance excitation spectra of BaF were recorded using two single-mode cw dye lasers. In the 30 000-cm?1 region, the electronic states observed were E2Σ+ and F2Π. The latter had been previously assigned as the “F2Σ+” state by Fowler [Phys. Rev.59, 645–652 (1941)]. The (3, 0) and (4, 0) bands of the E2Σ+-B2Σ+ transition and the (1, 0) and (2, 0) bands of the F2Π-B2Σ+ transition were rotationally analyzed. The molecular constants suggest inferences about the dominant atomic orbital character of the Rydberg molecular orbitals responsible for the E2Σ+ and F2Π electronic states. A new electronic state, the E′ 2Π, is predicted. The molecular parameters obtained (in cm?1, 1σ uncertainty in parentheses) are
X2Σ+A2ΠB2Σ+
Te015 958.41 (10)16 383.137 (6)
ωe285.732 (9)288.56 (20)285.747 (9)
ωeχe0.840 (4)0.954 (4)
Be0.094466141 (30)0.0957343 (20)0.0965151 (20)
αe0.000403551 (40)0.0004327 (20)0.0004483 (15)
γe (spin-rot.)0.00301484 (50)0.068767 (79)
Pe?0.066834 (64)
Ae59.175 (1)
  相似文献   

4.
张小妞  施德恒  孙金锋  朱遵略 《中国物理 B》2011,20(4):43105-043105
The potential energy curves (PECs) of X1Σ+g and A1Πu electronic states of the C2 radical have been studied using the full valence complete active space self-consistent field (CASSCF) method followed by the highly accurate valence internally contracted multireference configuration interaction (MRCI) approach in conjunction with the aug-cc-pV6Z basis set for internuclear separations from 0.08 nm to 1.66 nm. With these PECs of the C2 radical,the spectroscopic parameters of three isotopologues ( 12C2 ,12C13C and 13C2 ) have been determined. Compared in detail with previous studies reported in the literature,excellent agreement has been found. The complete vibrational levels G(υ),inertial rotation constants B υ and centrifugal distortion constants D υ for the 12C2 ,12C13C and 13C2 isotopologues have been calculated for the first time for the X1Σ+g and A1Πu electronic states when the rotational quantum number J equals zero. The results are in excellent agreement with previous experimental data in the literature,which shows that the presented molecular constants in this paper are reliable and accurate.  相似文献   

5.
6.
The difference of the energies of levels Δ n = E lev(2+0 n ) − E lev(0+0 n ) at n = 1, 2, and 3 and the multipole-mixture parameter δ for (2+02−2+01) and (2+03−2+01) transitions are contrasted against the structure of the K π = 02+ and 03+ rotational bands that was calculated on the basis of the quasiparticle-phonon model. The values of (Δ2 − Δ1), (Δ3 − Δ1), and (Δ2 − Δ3) are found to correlate with the sign of the parameter δ and with the calculated structure of the K π = 02+ and 03+ bands. Original Russian Text ? A.M. Demidov, L.I. Govor, V.A. Kurkin, I.V. Mikhailov, 2009, published in Yadernaya Fizika, 2009, Vol. 72, No. 2, pp. 236–240.  相似文献   

7.
The potential energy curves (PECs) of three low-lying electronic states (X~1Σg~+,w~3△u,and W~1△u) of P2 molecule are investigated using the full valence complete active space self-consistent field (CASSCF) method followed by the highly accurate valence internally contracted multireference configuration interaction (MRCI) approach in conjunction with the correlation-consistent basis set in the valence range.The PECs of the electronic states involved are modified by the Davidson correction and extrapolated to the complete basis set (CBS) limit.With these PECs,the spectroscopic parameters of the three electronic states are determined and compared in detail with the experimental data.The comparison shows that excellent agreement exists between the present results and the available experimental data.The complete vibrational states are computed for the w~3△u and W~1△u electronic states when the rotational quantum number J equals zero and the vibrational level G(v),the inertial rotation constant Bv,and the centrifugal distortion constant Dv of the first 30 vibrational states are reported,which accord well with the experimental data.The present results show that the two-point extrapolation scheme can obviously improve the quality of spectroscopic parameters and molecular constants.  相似文献   

8.
The behavior of the relative permittivity ɛ/ɛ0 of PbZr1 − x Ti x O3 (PZT) solid solutions (0.495 ≤ x ≤ 0.51) in the temperature range of 100–300 K at frequencies from 1 × 10−2 to 2 × 107 Hz was investigated. Diffuse, strongly relaxing maxima at T = 230−260 K (x = 0.495−0.505) and 150–160 K (x = 0.510) were observed in the PZT studied. The relaxation processes are well described by the Vogel-Fulcher law, and the dielectric spectra are approximated by the Cole-Cole formula.  相似文献   

9.
The weighted total cross section (WTCS) theory has been applied to the electron-H2 collision to obtain excitation, ionisation and dissociation cross section and rate coefficients of the X 1Sg+^{1}\!\Sigma _{g}^{+}, c 3Pu^{3}\!\Pi _{u}, a 3Sg+^{3}\!\Sigma _{g}^{+}, e $^{3}\!\Sigma _{u}^{+}$^{3}\!\Sigma _{u}^{+} and B 1Su+^{1}\!\Sigma _{u}^{+} states. Calculation has been performed in the temperature range 1500 K–15000 K. Rate coefficients are calculated from WTCS assuming Maxwellian energy distribution functions for electrons and heavy particles. Thermal equilibrium results are presented and fitting parameters (a, b and c) are given for each reaction rate coefficient: k(θ) = a (θb) exp(-c/θ).  相似文献   

10.
For the first time, the reactions π+p→K++ and K?p→π?+ have been studied in the same apparatus. This has been done at an adequately high momentum (10.1 GeV/c) to allow a check of the prediction of exchange degeneracy, that the differential cross sections should be converging at high energy. We have measured the cross section for momentum transfers t between tmin and t = ?0.3 (GeV/c)2. We find that for both reactions the differential cross section shows an exponential fall, with no deviations right in to t =tmin (where some other experiments have shown a dip in the cross section). Furthermore, we find the magnitude of the differential cross sections to be closely similar at t = 0, with a ratio
R=(dσdt)t=0(K?p→π?+)(dσdt)t=0+pK++
However, the slope for the positive reaction is about 19% steeper than that for the negative reaction.  相似文献   

11.
12.
Trivalent rare earth ions doped borosulfophosphate glasses are in high demand owing to their several unique attributes that are advantageous for applications in diverse photonic devices. Thus, Sm3+ ion doped calcium sulfoborophosphate glasses with composition of 25CaSO4–30B2O3–(45?x)P2O5xSm2O3 (where x?=?0.1, 0.3, 0.5, 0.7 and 1.0 mol%) were synthesized using melt-quenching technique. X-ray diffraction confirmed the amorphous nature of the prepared glass samples. Differential thermal analyses show transition peaks for melting temperature, glass transition and crystallization temperature. The glass stability is found in the range 91?°C to 116?°C which shows increased stability with addition of Sm2O3 concentration. The Fourier transform infrared spectral measurements carried out showed the presence of vibration bands due to PO linkage, BO3, BO4, PO4, POP, OPO, SOB, and BOB unit. Glass density showed increase in value from 2.179 to 2.251?g cm?3 with increase in Sm2O3 concentration. The direct, indirect band gap and Urbach energy calculated were found to be within 4.368–4.184?eV, 3.641–3.488?eV and 0.323–0.282?eV energy ranges, respectively. The absorption spectra revealed ten prominent peaks centered at 365, 400, 471, 941, 1075, 1228, 1375, 1477, 1528 and 1597?nm corresponding to 4D3/2,6H5/24I11/2,6P3/2, 6F11/2, 6F9/2, 6F7/2, 6F5/2, 6F3/2, 6H15/2 and 6F1/2 transitions respectively. Photoluminescence spectra monitored at the excitation of 398?nm exhibits four emission bands positioned at 559, 596,643 and 709?nm corresponding to 4G5/26H5/2, 6H7/2, 6H9/2 and 6H11/2 transitions respectively. The nephelauxetic parameters calculated showed good influence on the local environment within the samarium ions site and the state of the SmO bond. The Judd–Ofelt intensity parameters calculated for all glass samples revealed that Ω6?>?Ω4?>?Ω2. The emission cross-section and the branching ratios values obtained for 4G5/26H7/2 transition indicate its suitability for LEDs and solid-state laser application.  相似文献   

13.
The signs of the experimental values of the multipole-mixture parameters δ are compared with the signs of = Σa i μ i for (2+02−2+01) and (2+03−2+01) transitions and with the signs of = Σa i [(μ i + μ ) or (μ − 1/2)] for (2+21−2+01) transitions in nonspherical even-even nuclei, where a i is the contribution of the ith pair of quasiparticles to the wave function for 2+02, 2+03, and 2+21 single-phonon states according to the quasiparticle-phonon model and μ is the magnetic moment for the corresponding Nilsson state. Original Russian Text ? A.M. Demidov, L.I. Govor, V.A. Kurkin, I.V. Mikhailov, 2009, published in Yadernaya Fizika, 2009, Vol. 72, No. 2, pp. 228–235.  相似文献   

14.
Laser-induced fluorescence of Cs2 molecules in the infrared (1.15–2.5 μm) and the visible (505–545 nm) regions has been observed using several excitation wavelengths from an argonion laser. Accurate molecular constants and potential energy curves for the pumped E1Σu+ state and the first excited gerade 1Π state are derived from more than 1300 fluorescence lines precisely measured with a high-resolution Fourier transform interferometer. The main molecular constants for the states are
v′EE2Σ+v′FF2Π
Tv′0329 767.32(1)129 997.29(1)
ΔGv′ + 123522.841(27)1522.553(2)
Be0.22990(22)0.22931(8)
αe0.00113(14)0.00108(2)
Av′156.9840(12)
pv′1?0.02426(6)
γv′3?0.17367(46)
  相似文献   

15.
The arrival directions of primary cosmic ray particles with energies E 0 ≥ 1019 eV and zenith angles θ ≤ 60° recorded on the Yakutsk array over the period 1974–2009 are analyzed. These events separated by different time intervals are shown to have different global anisotropies.  相似文献   

16.
通过碳酸钙、γ-三氧化二铝、氯化钙在氯气/氩气混合气气氛下的固态反应制备了一种氯负离子存储-发射功能材料[Ca24Al28O64]4+·(Cl-)3.80(O2-)0.10(C12A7-Cl-).通过离子色谱、电子顺磁共振、拉曼光谱验证,C12A7-Cl-材料中存储的负离子主要是氯负离子,浓度为(2.21±0.24)×1021 cm-3,此外还有小部分的氧二价负离子、氧负离子、氧分子负离子.这与通过飞行时间质谱得到的结果一致:从C12A7-Cl-材料表面发射出的负离子主要是氯负离子(大约90%),还有小部分的氧负离子和电子.材料结构和表观变化分别由X射线衍射和场发射扫描电子显微镜表征  相似文献   

17.
The results of our experimental study of the kinetics of formation of O2(1Σ) molecules in energy-exchange reactions O2(1Δ) + I(5 p,2 P 1/2) and O2(a,1Δ) + O2(a,1Δ) are presented. The ratio of rate constants was obtained for these reactions (4800 ± 300). Setting the rate constant of the deactivation of O2(1Σ) molecules on CO2 molecules at 4.1 · 10–13 cm3/s, we evaluated the rate constants for these reactions at a temperature of approximately 330 K: (1.7 ± 0.2) · 10−13 and (3.6 ± 0.5) · 10−17 cm3/s, respectively.  相似文献   

18.
Among all the 4478 classical isomers of C66, C66(C s :0060) with the lowest number of pentagon–pentagon fusions was predicted to be the most stable isomer, followed by isomers C66(C 2v :0011) and C66(C 2:0083). The infrared spectra and aromaticity of the most stable isomers were predicted. The relative stabilities of C66 isomers change with charges or doping of metals. The structures and relative stabilities of the most stable metallofullerenes were delineated and compared with experiment. Sc2@C66(C 2:0083) was predicted to be the most stable metallofullerene, although Sc2@C66(C 2v :0011) was observed. Charge-transfer from Sc2 to the fused pentagons and the bonding between these two moieties significantly decrease the strain energies caused by the pair of fused pentagons thereby stabilizing the fullerene cage.  相似文献   

19.
We calculate the masses and the pole residues of the heavy baryons Ω c 0(css) and Ω b (bss) with the QCD sum rules. The numerical values  GeV (or  GeV) and  GeV (or  GeV) are in good agreement with the experimental data.  相似文献   

20.
This paper systematically investigates the local distortion and electron paramagnetic resonance (EPR) parameter for CdCl 2 :V 2+ and CsMgX 3 :V 2+ (X=Cl, Br) systems on the basis of the complete energy matrix, in which not only the contributions due to the spin–orbit coupling of the central ions but also that of the ligands are considered. To describe the difference of overlapping between d-orbits and p orbit, two spin–orbit coupling coefficients are introduced. By simulating the crystal field parameter and EPR parameter, the local distortion parameters are studied and the relationships between the EPR parameter and the spin–orbit coupling coefficients as well as divergent parameter are discussed. These results show that the local structures exhibit compression distortion for CdCl 2 :V 2+ and elongation distortions for CsMgX 3 :V 2+ (X=Cl, Br), respectively. It notes that the empirical formula R ≈ R H + (r i-r h )/2 is not suitable for CdCl 2 :V 2+ and CsMgX 3 :V 2+ (X=Cl, Br) systems. The contributions of ligand to spin–orbit coupling interaction cannot be neglected for strong covalent systems, especially for V 2+ doped in CsMgBr 3 :V 2+ .  相似文献   

Te (cm?1)ωe (cm?1)Be (cm?1)Re (A?)
E1Σu+20195.2329.100.008915.340733
(1) 1Πg13913.4218.440.007815.697722
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