共查询到20条相似文献,搜索用时 15 毫秒
1.
David M. Hirst 《Chemical physics letters》1979,65(1):181-183
Ab initio configuration-interaction calculations using a 9s5p|3s2p gaussian basis supplemented with polarization functions are presented for potential curves for the a 1Σ+ and the lowest 3Π state of CN+. The two states are very close in energy and calculations at this level do not give an unequivocal indication of the identity of the ground state. 相似文献
2.
Two mechanisms for the predissociation of the C2Σu+ state of N2+ are discussed - the accidental mechanism and a direct, homogeneous process C → B2Σu+. The matrix elements for the latter channel are dominated by a contribution from the nuclear kinetic energy operator, containing a Franck-Condon integral of form 〈?|?/?R|υ′〉. 相似文献
3.
A CAS SCF calculation of the potential surfaces for the lowest states of the O3+ ion is reported. An assignment of the bands in the HeI photoelectron spectrum is based upon calculated vibration profiles. This assignment shows the ground state of the ion to have 2B2 symmetry. Also the weak bands at 15.6, 16.5 and 17.5 eV are reassigned. 相似文献
4.
A new method of detecting vibration-rotation transitions in HD+ is described. The ion-beam laser-resonance method employs Doppler tuning and relies upon the detection of infrared photodissociation of levels close to the dissociation limit of HD+. Measurements of nine rotational components of the v = 18 ? 16 band are described. A review of the theoretical methods for the calculation of energy levels in HD+ is given, followed by a comparison of the experimental results with the best available theoretical values. The resolution of structure arising from proton hyperfine interaction is also described. 相似文献
5.
Non-empirical SCF and Cl calculations for the HN2+ molecule ion are reported. Potential curves for ground and excited states of this system are obtained, with particular emphasis on the manner in which these species dissociate upon NH stretch. The electronic spectrum of HN2+ is also calculated and compared with that of an unperturbed N2 molecule. 相似文献
6.
Cross sections for the photodissociation of ground state CH+ ions through absorption into the A1Π state are calculated for the lowest three vibrational levels. At threshold the cross sections for υ″ = 0, 1 and 2 are respectively 5.0 × 10?20 cm2, 8.1 × 10?19 cm2 and 2.6 × 10?18 cm2. 相似文献
7.
Laser-induced fluorescence of CsH from the A1Σ+ electronic state to the X1Σ+ state was recorded using high-resolution Fourier transform spectrometry. Ground-state vibrational levels were observed from ν″ = 1 to the dissociation limit. These measurements showed anomalies in the X1Σ+ potential energy curve due to the avoided crossing of ionic and covalent potential curves. Accurate molecular constants were derived for the lower X1Σ+ vibrational levels. The observation of a quasibound level gave the first experimental determination of the dissociation energy (in cm?1): 14802 ? Dc ? 14813. 相似文献
8.
Potential curves for the CH+ X1Σ+ and A 1Π states are constructed using the best experimental and theoretical information. The A 1Π curve is used to calculate the locations and widths of rotationally quasi-bound levels. Oscillator strengths from v'' = 0 of the X state to the shape resonances are also calculated. The results are in good agreement with experiment. 相似文献
9.
Dynamics of the reaction B+(3P) + H2 → BH+ + H has been studied in crossed-beam scattering experiments in the collision-energy range 0.6–2.3 eV (c.m.). Scattering diagrams obtained show that in the reaction both the ground state BH+(2Σ+) and the excited state BH+(2 Π) (if energetically accessible) are formed; both states are formed via intermediate complexes whose mean lifetimes are of the order of 10?13 s and decrease with increasing collision energy, as reflected in the decreasing forward-backward symmetry of the scattering diagrams. 相似文献
10.
Near Hartree-Fock level ab initio molecular orbital calculations on H3O+ and a minimum energy structure with θ(HOH) = 112.5° and r(OH) = 0.963 Å and an inversion barrier of 1.9 kcal/mole. By comparing these results to calculations on NH3 and H2O, where precise experimental geometries are known, we estimate the “true” geometry of isolated H3O+ to have a structure with θ(HOH) = 110-112°, r(OH) = 0.97–0.98 Å and an inversion barrier of 2–3 kcal/mole. Our prediction for the proton affinity of water is ≈ 170 kcal/mole, which is somewhat smaller than the currently accepted value. 相似文献
11.
The small magnitude and positive sign of the sodium atom hyperfine splitting constant of the Na+furil? radical triple ion is interpreted by elementary MO arguments. The model gives some insight into the nature of the Na—O coordination in such species. 相似文献
12.
The extension of the Jahn-Teller distortion of the SnH4+ structure is estimated from ab initio SCF CI calculations using pseudopotential atomic approximation with and without relativistic correction. These calculations show the lowest minima of SnH4+ to have C2v symmetry and are very close to the C3v minima. The calculated photoelectron spectrum of SnH4 is in good agreement with the experimental values. 相似文献
13.
Ab initio SCF MO energies and pair polarizabilities are reported for the pairs Li+/Li+ and Cl?/Cl? over the ranges of internuclear separation which are of importance in molten LiCl. The shapes of the β(R) curves resemble those of inert gas diatoms. The Cl?/Cl? interaction is predicted to make a rather small contribution to those properties of molten LiCl which depend on (2)(R), and a larger contribution to properties which depend on β(R). The Li+/Li+ interaction contributes almost nothing to the bulk polarizability. 相似文献
14.
The ratio of N4+ to N3+ formed in the radiolysis of gaseous nitrogen has been measured to be 4.7 ± 0.4 using a time-resolved atmospheric pressure ionization mass spectrometer. The limit of error has been evaluated from the ion mass discrimination of the apparatus. 相似文献
15.
E. Makrlík P. Selucky P. Vaňura P. Toman R. Rathore 《Journal of Radioanalytical and Nuclear Chemistry》2011,287(2):497-500
From extraction experiments and γ-activity measurements, the extraction constants corresponding to the general equilibrium M+(aq) + 1·Cs+(nb)
\rightleftarrows \rightleftarrows
1·M+(nb) + Cs+(aq) taking part in the two-phase water–nitrobenzene system (1 = hexaarylbenzene-based receptor; M+ = H3O+, NH4
+, Ag+, K+, Rb+, Tl+; aq = aqueous phase, nb = nitrobenzene phase) were evaluated. Furthermore, the stability constants of the ML+ complex species in nitrobenzene saturated with water were calculated; they were found to increase in the series of Rb+ < K+ < Ag+, Tl+ < H3O+, NH4
+. 相似文献
16.
Ab initio calculations in the “first-order wavefunction” CI approximation have been performed for several states of N2+ with 2Σu+, 2Σu?, 4Πu symmetry. A calculation of the electronic factor of the vibronic interaction between the B2Σu+ and C2Σu+ states seems to support the suggestion of Tellinghuisen and Albritton that the C state is predissociated by the continuum of the B state through nuclear momentum coupling. 相似文献
17.
A.W. Castleman 《Chemical physics letters》1978,53(3):560-564
Thermodynamic data are reported for NH3 clustered about Bi+, Rb+, and K+ in the gas phase. Unusually strong bondings of NH3 to Bi+ suggests the probable importance of partial covalent bonding in stabilizing the first ligand cluster. Differences in relative bond strengths for NH3 and H2O about Rb+ andK+ are consistent with the results of extended Hückel calculations reported herein. 相似文献
18.
W. Kołos 《Chemical physics letters》1975,31(1):43-45
The Born—Oppenheimer energy of H2 in the a 3Σg+ state has been improved. The new result, with estimated values of the relativistic and nonadiabatic corrections, and with the previously computed adiabatic corrections yields T0 = 95077.3 cm?1 in a good agreement with the recent experimental value T0 = 95076.4 ± 0.5 cm?1 of Miller and Freund. 相似文献
19.
Luminescence emission and uv-excitation properties of LaOBr: Tb3+, LaOBr: Ce3+, and LaOBr: Tb3+, Ce3+ phosphors were studied. The visible emission spectra of La0.995Tb0.005OBr consists of5D3,4 →7F3–6 transitions in the wavelength range of 410–630 nm. The excitation of the Tb3+ ion gives a broad 4f → 5d transition band at 254 nm and weaker4f → 4f transition lines above 300 nm. The uv-excitation and emission of La0.995Ce0.005OBr at 290, 315, 355 (excitation), and 440 nm (emission) originate from transitions between the 4f-ground state and the four crystal field components of the5d2D excited state. The sensitization of Tb3+ luminescence in LaOBr with Ce3+ at varying concentrations is described and discussed. With increasing Ce3+ concentration the 5D3 →7F transitions of Tb3+ quench totally and the5D4 →7F transitions begin to quench gradually. The excitation spectrum of the5D4 →7F5 transition of Tb3+ consists of four bands due to Tb3+ and Ce3+, of which the three Ce3+ bands increase in intensity and the Tb3+ band decreases as the Ce3+ concentration is increased. 相似文献
20.
The HCl+ (A) vibrational state distributions from the title reaction were studied over the 48–110 meV collision energy range. The and ratios increase by factors of about 1.3 and 2.5, respectively. The branching ratios appear to be determined primarily by Franck-Condon factors, and by the endoergicity of the ν′ = 2 level. 相似文献