共查询到20条相似文献,搜索用时 531 毫秒
1.
The first accurate studies on the vibrational spectroscopic constants and the corresponding full vibrational energy spectra
of some electronic states of diatomic molecular ions XY+ were performed using algebraic method(AM). The AM is applied on the X1Σ+ state of BeH+, the X2Σ+ state of CO+, the X2Πg state of F
2
+
, the A2Πu state of O
2
+
and the X2Σ
g
+
state of Li
2
+
. The results show that AM can generate accurate vibrational spectroscopic constants as well as accurate full vibrational
energy spectra by using some accurate experimental vibrational energies, and that the AM vibrational energies are better than
other theoretical data.
__________
Translated from Chinese Journal of Atomic and Molecular Physics, 2005, 22 (4) (in Chinese) 相似文献
2.
N. Kaiser 《The European Physical Journal A - Hadrons and Nuclei》2007,31(2):207-212
We calculate at two-loop order in chiral perturbation theory the electromagnetic corrections to the leading-order 2π exchange
NN interaction proportional to g
A
0 and g
A
2. The resulting 2πγ exchange potential contains isospin-breaking components which reach up to about -2% of the corresponding
isovector 2π exchange potential. With a value of only -17keV at r = m
π
-1 = 1.4fm the charge-independence breaking central potential obtained here is negligibly small in comparison to the one generated
by the isoscalar c3 contact vertex. Our calculation confirms that the largest long-range isospin-violating NN potentials arise from the 2πγ exchange diagrams involving the large low-energy constants c
4 ≃ - c
3 ≃ 3.3GeV^-1 representing the important Δ(1232) dynamics. 相似文献
3.
A. Pashov P. Popov H. Knöckel E. Tiemann 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2008,46(2):241-249
We report on high resolution Fourier-transform spectroscopy of fluorescence to the a3Σu
+ state induced by two-photon or two-step excitation from the X1Σg
+ state to the 23Πg state in the molecule K2. These spectroscopic data are combined with recent results of Feshbach resonances and two-color photoassociation spectra
for deriving the potential curves of X1Σg
+ and a3Σu
+ up to the asymptote. The precise relative position of the triplet levels with respect to the singlet levels was achieved
by including the excitation energies from the X1Σg
+ state to the 23Πg state and the frequencies of the fluorescence down to the a3Σu
+ state in the simultaneous fit of both potentials. The derived precise potential curves allow for reliable modeling of cold
collisions of pairs of potassium atoms in their 2S ground state.
Electronic supplementary material Supplementary Online Material 相似文献
4.
5.
The analytical potential energy functions have been calculated for the ground state X1Σ+g and four excited electronic states a1Πg, A3Σ+u, B′3Σ?u and B3Πg of N2 molecule using the algebraic and energy-consistent methods (AM-ECM). Based on our previously published full AM vibrational energies and spectroscopic constants, the low-lying force constants fn, the expansion coefficients an and the variational parameters λ in the AM–ECM potentials are determined for these states. The computed AM–ECM potential energy curve of each state is in excellent agreement with the experimental data and better than other analytical potentials. 相似文献
6.
基于计算双原子分子完全振动能谱及离解能的代数方法 (algebraic method,AM)和研究双原子分子解析势能函数的能量自洽法(energy consistent method,ECM),建立了计算双核分子体系精确解析势能函数的代数-能量自洽法(AM-ECM).应用AM-ECM方法研究了7Li+2-23Σg,KH-X1Σ+,NaLi-X1Σ+和NaLi-A1Σ+电子态的解析势能表达形式,并与其他方法的研究结果进行了比较,获得了能正确描述这些电子态在渐近区和离解区的精确解析表达结果. 相似文献
7.
V. G. Blinkova 《Russian Physics Journal》1974,17(11):1511-1514
A comparative study is made of four three-parameter semiempirical potential energy functions for 32 electronic states of diatomic molecules and their ions:n 2:X1gS g + ,B 3πg,A 3 gSu,C 3 u,B′ 3 gSu.a 1 πg, a′gS u ? ,Ω 1δu N 2 + :X 2 gS g gS +A 2 π,C 2 gS u + ,B 2 gS u + CO:X1gS+,a 3 π, a′3 gSu,e 3 gS?,d 3gD1,A 1π CO+:X2gS+,A 2 π,B 2gS+ O2:X3gS g ? ,B 3 gSu,c 1 gS u ? ,b 1gS g s ,a 1 δg,c 3 δu O 2 + :X 2πg,A 2 πg, a1 πg,b 4 gS g ? A program for numerically integrating the radial Schrödinger equation by the Cooley method is worked out. Certain additional units are introduced to conserve computer time. The resulting vibrational levels are compared with the experimental levels for all the electronic states studied. It is concluded on the basis of this analysis that it is not possible to describe equally well all the electronic states of various molecules on the basis of any single three-parameter potential function. A method for choosing a potential function for describing some particular electronic state of a diatomic molecule is proposed. 相似文献
8.
P. Jasik J. Wilczyński J. E. Sienkiewicz 《The European physical journal. Special topics》2007,144(1):85-91
We report adiabatic potential energy curves of the
Li2
+ molecule. Our curves are tabulated according to
internuclear distance from 2 a0 to 100 a0. We
compare our theoretical results with the ones calculated by other
authors and potential energy curves derived from experiments. For
the ground state and 17 excited states we calculate spectroscopic
parameters and compare them with parameters obtained by other
authors. For the first time we present three new minima for
32Σu
+, 42Σu
+ and 22Πg
excited states. In our approach we use the configuration interaction
method where only the valence electrons of Li atoms are treated
explicitly. The core electrons are represented by pseudopotential.
All calculations are performed by means of MOLPRO program package. 相似文献
9.
Ye. V. Baklanov V. P. Chebotayev 《Applied Physics A: Materials Science & Processing》1977,13(1):97-99
First cw laser oscillation with thresholds below 1 mW was observed for various B1Пu → X1
∑
g
+
transitions of diatomic molecular sodium excited by different argon laser lines in the range of 454–488 nm. For pump powers
of 0.5 W output powers up to 3 mW and single-pass gain up to 0.1 cm−1 were obtained. Some properties of the heat pipe laser system are discussed. 相似文献
10.
Alternative expressions for vibrational and rotational spectrum constants and energies of diatomic molecular electronic states based on perturbation theory are suggested. An algebraic method (AM) is proposed to generate a converged full vibrational spectrum from limited energy data, and a potential variational method (PVM) is suggested to produce the vibrational force constants fn and rotational spectrum constants using the perturbation formulae and the AM vibrational constants. The AM and PVM have been applied to study 10 diatomic electronic states: the X1Σg+ and C1Πu− states of H2; the X1Σg+, A3Σu+, B′3Σu−, and B3Πg states of N2; the X3Σg−, A3Σu+, and c1Σu− states of O2; and the X1Σg+ state of Br2. Calculations show that (1) the AM Eυmax converges to the correct molecular dissociation energy; (2) the AM not only reproduce the input energies, but also generate the Eυ's of high vibrational excited states which may be difficult to obtain experimentally or theoretically; (3) the PVM vibrational force constants fn may be used to measure the relative chemical bondstrengths of different diatomic electronic states for a molecule quantitatively. 相似文献
11.
High-resolution spectra of the 0–9, 0–10 and 0–11 bands of theA
2II
u
—X
2II
g
system of (16O18O)+ ion have been studied for their rotational structure. This study enables a direct determination of the Λ-doubling parameters
of theA
2II
u
andX
2II
g
states. The model of ‘pure precession’ explains, though not entirely, the Λ-doubling of theX
2II
a
state as arising out of its interaction with theB
2
Σ
g
− state. The Λ-doubling in theA
2II
u
state was found insignificant. 相似文献
12.
L. Yu. Korotkova Yu. B. Gurov E. M. Kalinin V. S. Karpukhin S. V. Lapushkin V. G. Sandukovskii B. A. Chernyshev T. D. Shchurenkova 《Bulletin of the Russian Academy of Sciences: Physics》2012,76(4):400-403
The origin of the 9Li isotope is sought in missing-mass spectra measured in 11B(π−, d)X, 12C(π−, pd)X, and 14C(π−, dt)X stopped-pion absorption reactions. The parameters of the three observed low-lying excited states coincide with the literature
data. A state with excitation energy E
x
= 9.1 ± 0.1 MeV, lying above the threshold of 9Li decay into 6He + t, is observed for the first time. 相似文献
13.
14.
Yu. B. Gurov E. M. Kalinin V. S. Karpukhin L. Yu. Korotkova S. V. Lapushkin I. V. Laukhin P. V. Morokhov V. G. Sandukovsky B. A. Chernyshev 《Bulletin of the Russian Academy of Sciences: Physics》2011,75(4):459-462
A search for the 10Li formation was performed in missing mass spectra measured in stopped pion absorption reactions 14C(π
−, pt)X and 14C(π
−, dd)X. Three excited states of 10Li were found. The broad state with a resonance energy of E
R
= 6.13 ± 0.11 MeV has the highest excitation energy in comparison with levels observed earlier. 相似文献
15.
Zhong Liu Yuhu Zhang Yingjun Ma Y. Sasaki K. Yamada H. Oshima H. Yokose M. Ishizuka T. Komatsubara K. Furuno 《中国科学G辑(英文版)》2003,46(4):390-397
Excited states of125Sb have been studied using in-beam γ spectroscopy techniques via the124Sn(7Li, α2n) reaction at a beam energy of 32 MeV. A high-spin level scheme including 21 new γ-transitions and 14 new excited states
have been established. Three isomers have been identified at 1970, 2110 and 2471 keV and the ranges of their half-lives have
been estimated from the delayed coincidence data. The level structure of125Sb is discussed in terms of particle-core excitation coupling. With the help of empirical shell model calculations the three
isomers are proposed to have three-quasiparticle πg7/2⊗v(h
11/2
s
1/2)5−, πg7/2⊗v(h
11/2
d
3/2)7− and πg7/2⊗v(h
112/2)10
+ configurations, respectively. 相似文献
16.
17.
B. P. Lavrov 《Russian Journal of Physical Chemistry B, Focus on Physics》2012,6(2):239-248
A statistical analysis of all the available data on the wave numbers of spectral lines related to triplet-triplet electronic-vibrational-rotational
(rovibronic) radiation transitions into the H2 molecule (1sσ2sσ) a
3Σ
g
+ electronic state was performed for the first time. This allowed us to check and refine the controversial identification of
several spectral lines. Optimum rovibronic term values were found for 15 electronic states, including the (4pσ)f
3Σ
u
+, (4pπ)k
3Π
u
+, and (4pπ)k
3Π
u
− states studied in this work. The ratios between the oscillator strengths of R- and P-branch lines with common upper levels (branching coefficients) for the f
3Σ
u
+ → a
3Σ
g
+ and k
3Π
u
+ → a
3Σ
g
+ systems of H2 molecule bands were measured for the first time. Substantial deviations of the measured branching coefficients from the corresponding
ratios between the Henl-London factors were observed. The deviations monotonically increased as the rotational quantum number
N grew, which, in combination with substantial Λ-doubling in the k
3Π
u
state, was evidence of an important role played by electronicrotational interaction in the 4pσ3Σ
u
+ and 4pπ3Π
u
+ adiabatic electronic states. A strong correlation was observed between the N dependences of branching coefficients for transitions from the mutually perturbed f
3Σ
u
+ and k
3Π
u
+ electronic states. The results of this work show that the measured branching coefficients are a much more sensitive and capacious
channel of information about perturbation effects than rovibronic term values. 相似文献
18.
Yu. B. Gurov E. M. Kalinin V. S. Karpukhin S. V. Lapushkin I. V. Laukhin V. A. Pechkurov V. G. Sandukovsky B. A. Chernyshev T. D. Shchurenkova 《Bulletin of the Russian Academy of Sciences: Physics》2010,74(4):433-436
The results from an experimental search for the production of heavy lithium isotopes 11,12Li in stopped π−-meson absorption reactions on a 14C radioactive target are presented. A pronounced peak is observed in the missing mass spectrum of the 14C(π−, pp)X reaction, which is associated with the formation of a nucleon-unstable 12Li state with the following resonance parameters: E
R
= 4.0 ± 0.2 MeV and Γ = 1.1 ± 0.2 MeV. Resonance parameters of three low-lying 11Li excited states were determined in the 14C(π−, pd)X, reaction. 相似文献
19.
Summary We show how conventional linear expansion techniques for both electronic and vibrational wave functions can be used for the
computation of matrix elements governing the two-photon absorption probability in molecules. In particular, the2Σ+
A←2∏X transition matrix elements of OH and the1Σ
g
+
E,F←1Σ
g
+
X of H2are computed using 1) the sum over states in the Born-Oppenheimer approximation with inclusion of vibrational wave functions,
2) solution of perturbation theory equations by expansion in the CI basis at fixed nuclei, followed by a kind of vibrational
averaging. The results are compared with experiment and discussed.
To speed up publication, the authors of this paper have agreed to not receive the proofs for correction. 相似文献
20.
X. G. Wu M. J. Wan C. Q. Song T. Gao 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2010,60(2):263-267
Electronic structure and spectroscopic properties B
e, ωe, ωe
x
e, αe, T
e
of ground state and the low-lying excited states of HF+ and HF- molecular ions were
investigated within scalar relativistic multireference configuration
interaction with single and double excitations framework using the GAMESS-US
program package. All potential energy curves (PECs) were calculated using
the relativistic complete active space self-consistent field/spin-orbit
multi-configuration quasi-degenerate perturbation theory (CASSCF/SO-MCQDPT).
The curves are all fitted to the analytical potential energy function
(APEF), from which accurate spectroscopic constants are derived. The
spin-orbit splitting was also been studied, the split value of X2P^{2}{\rm \Pi} state of HF+ is determined to be 288.38 cm-1. The calculated properties are in good agreement with the available experimental value.
Spectroscopic constants of the ground states of HF- that have never
been observed in experiment are obtained. These curves provide an
interpretation of the known experimental observations on this system and
suggest a number of further experiments which possible provide a critical
test of this data. 相似文献