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1.
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   

2.
王杰敏  冯恒强  孙金锋  施德恒 《中国物理 B》2012,21(2):23102-023102
The potential energy curves (PECs) of three low-lying electronic states (X1Σg+, w3Δu, and W1Δu)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 w3Δu, and W1Δu 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   

3.
高虹 《物理学报》1997,46(11):2138-2145
运用量子亏损理论,并与参考系变换及本征通道R-矩阵法相结合,建立了描述氢分子里德伯态的预解离过程的理论方法.通过对氢分子的3pπD1πu+和4pσ B″1Σu+电子态的预解离过程的研究,阐明其解离的机理,并给出预解离的线宽. 关键词:  相似文献   

4.
用4415.6?CW激光线获得了5730?附近的K2分子23g—13u+漫射荧光谱。实验研究了缓冲气体Ar气压强P对漫射谱峰值强度Idiff的碰撞诱导增强效应。用稳态碰撞模型描述了C1u—23g间的能量转移过程,推导出了Idiff-P函数关系,对实验数据进行了令人满意的拟合。这种拟合表明:适当变更实验装置,利用本文模型可以得到C1u—23g间的能级交叉速率和碰撞诱导转移速率。 关键词:  相似文献   

5.
吕燕南  黄祖洽 《物理学报》1989,38(9):1510-1514
采用显含电子对相关坐标的波函数,在微扰论的框架下计算了Elg+态氢分子与基态氢分子取cross构型时的中长程相互作用。结果表明,该相互作用在分子间距6.5α0附近存在着一个活化能势垒,在4.5α0附近显示出较强的化学键行为。 关键词:  相似文献   

6.
刘慧  邢伟  施德恒  孙金锋  朱遵略 《物理学报》2012,61(20):205-212
采用Davidson修正的内收缩多参考组态相互作用方法及Dunning等的相关一致基aug-cc-pV6Z计算了B2分子X3g-和A3Πu电子态的势能曲线.利用总能量外推公式,将两个电子态的总能量分别外推至完全基组极限.对势能曲线进行核价相关修正及相对论修正计算,得到了同时考虑两种效应修正的外推势能曲线.通过同位素质量识别,得到了主要的同位素分子11B11B和10B11B的X3Σg-和A3u电子态的光谱常数Te,Reeexeeye,Bee和γe.求解双原子分子核运动的径向Schr(o|¨)dinger方程,找到了无转动的同位素分子11B2(X3Σg-,A3Πu)和10B11B(X3g-,A3Πu)的全部振动态.针对每一同位素分子的每一振动态,分别计算了其振动能级和惯性转动常数等分子常数,它们均与已有的实验结果较为一致.其中,10B11B(AΠu)分子的光谱常数和分子常数属首次报道.  相似文献   

7.
The 7Li2 51Σg+ and 61Σg+ states have been studied both experimentally and theoretically. Vibrational levels v=1-26 of the 51Σg+ state and v=2-14 of the 61Σg+ state were observed using pulsed optical-optical double resonance technique. The 51Σg+ state has an unusual potential energy curve with a shelf near v=11. Dunham coefficients for the v=0-9 levels of the 51Σg+ state have been obtained. RKR potential energy curves of these two were generated. Ab initio potentials are in good agreement with the RKR potentials.  相似文献   

8.
The emission spectrum of InBr molecule has been recorded in the region 350–400 nm on BOMEM DA8 Fourier transform spectrometer at an apodized resolution of 0.06 cm−1 using microwave excitation technique. About 61 violet degraded and single headed bands have been recorded and are classified into two band systems, viz. A3Π0-X1Σ+ and B3Π1-X1Σ+. A few new bands have been observed and are fitted in the vibrational schemes of the two systems. Revised vibrational constants have been determined. The vibrational assignments have been confirmed by observing isotope effect due to InBr81 in the 30 bands of the A3Π0-X1Σ+ system and 19 bands of the B3Π1-X1Σ+ system. The analysis is further supported by calculating the Franck-Condon factor for InBr79 and InBr81 molecules. The following vibrational constants (in cm−1) have been determined from the analysis:   相似文献   

9.
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   

10.
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   

11.
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
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   

12.
Optical heterodyne magnetic rotation enhanced velocity modulation spectroscopy was employed to observe the visible absorption spectra of the B^2Σ^+_u-X^2Σ^+_g electronic transition of C^-_2. Four hot bands (0,1), (1,2), (2,3) and (3,4) have been observed and the band (3,4) is measured directly for the first time, so far as we know, by absorption. A rotational analysis was carried out to obtain molecular constants. With the Franck-Condon principle and the vibrational Boltzmann distribution, we have estimated the vibrational temperature of C^-_2 to be about 3000K.  相似文献   

13.
使用对称性匹配簇-组态相互作用方法首次计算了Li2分子自旋一致激发态a3Σ+u和b3Πu的离解能、平衡几何及其谐振频率。使用最小二乘法、利用Murrell-Sorbie函数形式拟合出了Li2分子三重态的第一激发态a3Σ+u 和第二激发态b3Πu的完整势能函数,并计算了这两个态的光谱常数 (Be, αe, ωe 和 ωeχe) 和力常数 (f2, f3和f4)。得到了Murrell-Sorbie函数形式既适用于基态、又适用于激发态的结论。将计算得到的激发态(a3Σ+u和b3Πu)的离解能、平衡几何及其谐振频率与实验结果及其它理论计算结果进行了比较。从比较的结果中可以清楚地看出,本文的计算结果在计算精度方面有很大的改进。  相似文献   

14.
Magnetoresistive ceramic samples La0.7Ca0.3 − x Sr x MnO3 ± δ sintered at temperatures of 1150 and 1350°C are investigated using X-ray diffraction, microscopic, resistance, and magnetic (χ, 55Mn NMR) measurements. The specific features of the influence of the composition on the type and parameters of the perovskite structure, its imperfection, the porous crystallite structure, the metal-semiconductor and ferromagnetic-paramagnetic phase transitions, the 55Mn NMR spectra, and the magnetoresistance effect are established. The magnetic phase diagram is constructed. The conclusions are drawn regarding the nonuniformity of the distribution of ions and vacancies around manganese involved in the high-frequency electron-hole exchange (Mn3+ ai Mn4+) and the nanostructured separation of the perovskite structure containing anion and cation vacancies, with the concentrations and magnetoresistance effect decreasing and the lattice parameters and phase transition temperatures increasing as calcium is replaced by strontium. Original Russian Text ? A.V. Pashchenko, A.A. Shemyakov, V.P. Pashchenko, V.A. Turchenko, V.K. Prokopenko, Yu.F. Revenko, Yu.V. Medvedev, B.M. éfros, G.G. Levchenko, 2009, published in Fizika Tverdogo Tela, 2009, Vol. 51, No. 6, pp. 1127–1136.  相似文献   

15.
张中明  熊烨 《物理学报》1997,46(11):2124-2129
在双原子分子核运动的波动方程中,计入分子的振转相互作用项,得出的波函数除与振动量子数有关外,还与转动量子数有关.用该波函数编程序计算了BF分子A1Π→X1Σ+带系和b3Σ+→a3Π带系的Franck-Condon因子.计算中转动量子数的取值由J=0取至J=200,结果适用于低温、高温和强激波条件. 关键词:  相似文献   

16.
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   

17.
实验利用TN-1710光学多道分析系统(OMA),对H1+,H2+,H3+和He,Ne,Ar碰撞过程中产生的巴耳末系Hα,Hβ,Hγ发射进行了测量,入射离子H1+,H2+,H3+关键词:  相似文献   

18.
The unitarization of the amplitude for the decay process K 10 → π+π and allowance for the rescattering of final-state pions in the decay process K + → π+π+π make it possible to evaluate, by using the parameters extracted from data on K → 2π decays, the K + → π+π+π decay width. The result agrees with the experimental width value at a level of a few percent. Allowance for corrections for higher order terms of the momentum expansion of the amplitude for the decay process K + → π+π+π leads to the slope-parameter value of g ++−th = 0.2182, which agrees with its experimental counterpart, g ++−exp = 0.2154 ± 0.0035.  相似文献   

19.
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   

20.
利用铝电极放电产生的Al原子与O2反应生成AlO自由基,在超声射流冷却下在43 0—480nm波长范围观测到AlO自由基B—X跃迁的激光诱导荧光激发谱.光谱振动结构分析表明 所有的谱带属于V′-V″=1,2,3跃迁,并获得基态和激发态的振动频率与非谐性常数.另外还 对其中(1,4)谱带的转动结构进行标识,并得到相应的转动常数和离心畸变系数.对从基态 振动能级V″=5向上跃迁的谱带强度增强进行了讨论. 关键词: 光谱 AlO  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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