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81.
Band mixing calculations have been done for24Ne including the two degenerate prolate and oblate Hartree-Fock states and also some particle-hole excited states in the projection
formalism using an interaction obtained by Preedom and Wildenthal. The energy spectrum agrees very well with the experimental
results as well as the exact shell model calculations. Thus the band mixing calculations provide a good approximation to the
lengthy exact shell-model calcuations. In addition they offer a physical insight into the collective nature of the nucleus
as nuclear states are described in terms of only a few ‘intrinsic’ states. 相似文献
82.
An all-metal hollow-cathode laser tube consisting of a perforated cylindrical cathode surrounded by a coaxial cylindrical anode has been operated as a He?Ne laser at 0.6328, 1.15 and 3.39 μm, and as a He?Cd laser at red, green and blue visible wavelengths, using both de and pulsed-plus-dc excitation. Laser oscillation in He?Zn, Ne?Cd, Xe?Cd and Ar?Cd mixtures has also been obtained. The hollow-cathode discharge consists primarily of an intense cathode glow inside the cathode cylinder, giving a quiet, stable, low-voltage, positive-resistance discharge. Results for the He?Ne and He?Cd laser output versus partial and total pressures and discharge currents are presented. The unoptimized laser performance for the He?Ne case approaches but does not yet equal the conventional positive-column case, while the He?Cd performance for the charge-transfer-pumped green 5378Å line appears particularly promising. 相似文献
83.
A. Golovchenko S. P. Tretyakova A. Anne C. Tostain G. Tousset R. Bimbot F. Clapier B. Kubica R. Ili 《Radiation measurements》1995,25(1-4):107-110
The ranges and their dispersion for 77.1 and 95 MeV/n 20Ne ions in CR-39 track detector were measured and compared with those calculated by the TRIM-90.05 computer code. 相似文献
84.
The finite-field many-body perturbation theory limited to intermediate states involving single and double substitutions in the reference HF determinant is applied to the calculation of dipole polarizabilities of 10-electron atomic systems. The nuclear charge dependence of the convergence of the SD-MBPT series for correlation corrections to the dipole polarizability is investigated. It is concluded that the fourth-order SD-MBPT scheme is quite appropriate for neutral and positively charged species. For negatively charged systems the convergence of the SD-MBPT series becomes much poorer and including higher-order substitutions may be necessary. The role of the renormalization contributions to the SD-CI polarizability results is also considered. It follows that the corresponding data need to be corrected for the erratic treatment of unlinked clusters. The size inconsistency effects make quite important contributions to the SD-CI values of the correlation corrections to dipole polarizabilities. 相似文献
85.
Lin Wang Shunle Dong 《天然气化学杂志》2007,16(4):423-427
Lattice dynamical simulations of noble gas hydrate structuresⅠandⅡhave been performed. Potential energies were investigated to study the influence of guest species on the stability of the hydrate structure.Results show that when the diameter of inclusion molecules is between 3(?)and 4.2(?),such as Ar and Kr,the critical role of the 5~(12)cage in the stabilization of hydrates becomes effective.For Xe hydrates SⅠand SⅡ,with the help of lattice dynamical calcnlations,the modes attributions are identified directly.We proposed the resonant effect of the fingerprint frequency at about 7 meV and 10 meV which arise from the coupling of Xe molecules in the 5~(12)cage with the host lattice. 相似文献
86.
Minaev BF Kobzev GI 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2003,59(14):3387-3410
The Einstein coefficient for the singlet oxygen emission a1Deltag-->X3Sigmag- at lambda=1270 nm and b1Sigmag+-->X3Sigmag- emission at lambda=750 nm were calculated by quadratic response (QR) multiconfiguration self-consisted field (MCSCF) method for a number of collision complexes O2+M, where M=He, Ne, Ar. Interaction with He clusters was studied in order to simulate cooperative effect of the environment on the oxygen emission. Calculations of the dipole transition moment for the Noxon band, b1Sigmag+-a1Deltag, by linear response (LR) MCSCF method were also performed for a number of collision complexes. Spin-orbit coupling (SOC) between the b1Sigmag+ and X3Sigmag- (MS=0) states does not change much upon collisions, thus the a-X transition borrows intensity mostly from the collision-induced Noxon band b-a. The a-X intensity borrowing from the Schumann-Runge transition is negligible. The calculations show that the b-a and a-X transition probabilities are enhanced approximately by 10(5) and 10(3) times by O2+M collisions. An order of magnitude differences occur for both transitions for noble gases with large difference in polarizability. A strong cooperative effect is obtained when few He atoms perturb the oxygen molecule. Depending on mutual orientation of the partners it can be a complete quenching of the a-->X emission or strong non-additive enhancement. Collision-induced infrared vibrational transitions in a number of molecular oxygen excited states were studied and shown to be state selective. 相似文献
87.
Using a computer controlled version of the Ben-Naim and Baer apparatus, the solubilities of He, Ne, Ar, Kr, H2, D2, N2, O2, CH4, C2H6, C3H8, CF4, and SF6 in D2O (and the solubility of CF4 in H2O) were determined at four temperatures in the range 288 to 318 K and at a partial pressure of gas of 101.325 kPa. The precision of the measurements was 0.3–1.0%. The experimental data were processed using rigorous thermodynamic methods and were fitted to the Clarke-Glew-Weiss equation. Changes in the thermodynamic properties on solution were calculated from the smoothing equations. Scaled-particle theory (SPT) was used to determine the Lennard-Jones (6,12) pair potential parameters for D2O: =0.275 nm and /k=83.4 K. Experimental mole fraction solubilities and thermodynamic functions at 298.15 K were compared with results calculated using the SPT. The thermodynamic transfer functions of gases from H2O to D2O were calculated. The changes induced by the solvation process on the structure of water were estimated from the Gibbs energy of transfer and the difference in the hydrogen bond energies for D2O and H2O. 相似文献
88.
In the present investigation, holographic interferometry was utilized for the first time to measure in situ the thickness of the oxide film, alternating current (AC) impedance, and double layer capacitance of aluminium samples during anodization processes in aqueous solution without any physical contact. The anodization process (oxidation) of the aluminium samples was carried out by the electrochemical impedance spectroscopy (EIS), in different concentrations of sulphuric acid (1.0–2.5% H2SO4) at room temperature. In the mean time, the real-time holographic interferometric was used to measure the thickness of anodized (oxide) film of the aluminium samples in aqueous solutions. Also, mathematical models were applied to measure the AC impedance, and double layer capacitance of aluminium samples by holographic interferometry, during anodization processes in aqueous solution. Consequently, holographic interferometric is found very useful for surface finish industries especially for monitoring the early stage of anodization processes of metals, in which the thickness of the anodized film, the AC impedance, and the double layer capacitance of the aluminium samples can be determined in situ. In addition, a comparison was made between the electrochemical values obtained from the holographic interferometry measurements and from measurements of EIS. The comparison indicates that there is good agreement between the data from both techniques. 相似文献
89.
A new four-dimensional (4D) ab initio potential energy surface (PES) for Ne–CS2 involving the Q1 and Q3 normal modes for the ν1 symmetric stretching vibration and ν3 antisymmetric stretching vibration of CS2 is presented. The PES is constructed at the coupled-cluster singles and doubles with noniterative inclusion of connected triples [CCSD(T)]-F12 level with a large basis set including midpoint bond functions. Two vibrationally averaged potentials with CS2 at the vibrational ground and ν1 + ν3 excited states are generated from the 4D potential. Each potential contains a T-shaped global minimum and two equivalent linear local minima. The rovibrational energy levels and bound states are calculated employing radial discrete variable representation/angular finite basis representation and the Lanczos algorithm. In addition, the predicted band origin shift is 0.2514 cm?1 for Ne–CS2. The spectroscopic parameters are also predicted. 相似文献
90.
Ne-HCl势能面和振转光谱的理论研究 总被引:5,自引:0,他引:5
利用量子化学计算方法CCSD(T)和大基组aug-cc-pVTZ加键函数3s3p2d对Ne-HCl体系的分子间势能面进行了理论研究.结果表明,势能面上有两个势阱,分别对应于线性Ne-ClH和Ne-HCl构型.通过精确求解核运动方程发现,该从头算势能面分别支持5个(对Ne-HCl)和7个(Ne-DCl)振动束缚态.计算得到的振转跃迁频率与实值值吻合. 相似文献