A complete set of V–T (vibration–translation) relaxation rates and of dissociation coefficients for the system O–O2 have been obtained by using quasiclassical trajectories on the Varandas and Pais potential energy surface. The results, averaged on a Boltzmann rotational distribution, cover the whole range of the vibrational ladder and are reproduced in closed form ready to be implemented in state-to-state kinetic models. The accuracy of the results has been tested by comparing them with available experimental and theoretical values (ASI-CAST project is acknowledged). 相似文献
In this paper, a class of anisotropic Herz-type Hardy spaces associated with a non-isotropic dilation on ℝn are introduced, and the central atomic and molecular decomposition characterizations of those spaces are established. As some applications of the decomposition theory, the authors study the interpolation problem and the boundedness of the central δ-Calderón-Zygmund operators on the anisotropic Herz-type Hardy spaces. The research is supported by NSF of China (Grant Nos. 10571014 and 10571015) and SRFDP of China (Grant No. 20050027025) 相似文献
Let L be a one-to-one operator of type ω having a bounded H∞ functional calculus and satisfying the k-Davies-Gaffney estimates with k ∈ N. In this paper, the authors introduce the Hardy space HLp(Rn) with p ∈ (0, 1] associated with L in terms of square functions defined via {e-t2kL}t>0 and establish their molecular and generalized square function characterizations. Typical examples of such operators include the 2k-order divergence form homogeneous elliptic operator L1 with complex bounded measurable coefficients and the 2k-order Schrdinger type operator L2 := (-Δ)k + Vk, where Δ is the Laplacian and 0≤V∈Llock(Rn). Moreover, as an application, for i ∈ {1, 2}, the authors prove that the associated Riesz transform ▽k(Li-1/2) is bounded from HLip (Rn) to Hp(Rn) for p ∈ (n/(n + k), 1] and establish the Riesz transform characterizations of HL1p (Rn) for p ∈ (rn/(n + kr), 1] if {e-tL1 }t>0 satisfies the Lr-L2 k-off-diagonal estimates with r ∈ (1, 2]. These results when k := 1 and L := L1 are known. 相似文献
The behaviour of methane molecules inside carbon nanotubes at room temperature is studied using classical molecular dynamics simulations. A methane molecule is represented either by a shapeless super-atom or by a rigid set of five interaction centres localized on atoms. Different loadings of methane molecules ranging from the dense gas density to the liquid density, and the influence of flexibility of the CNT on structural and dynamic properties of confined molecules are considered. The simulation results show the decreases of the diffusion coefficient of methane molecules with density. At higher densities diffusion coefficient values are almost independent of molecular shape, but at low densities one observes faster motion of the super-atom molecule than that for the tetrahedral model of the molecule. For loadings of methane considered here the nanotube flexibility, introduced by the reactive empirical bond order (REBO) potential for interactions between carbon atoms of nanotube, does not have an effect on diffusivity of methane molecules, and its impact on the molecular structure is weak. It is found that methane molecules in the vicinity of the nanotube wall show tripod orientation with respect to the nanotube surface. 相似文献
The influence of molecular alignment and orientation on multiphoton vibrational excitation of diatomic molecules H2, HD, and D2 is studied by an analytical algebraic approach. The explicit expressions of the time-evolution operator and the excitation probability are given. The long-time average absorbed energy spectra and the time-dependent absorbed energy are obtained. Results show that the impact of molecular orientation on the multiphoton resonant excitation is decided by the molecular type and molecular anharmonicity. This is valuable for controlling the vibrational excitation of molecules, which is relevant to the whole field of molecular physics and physical chemistry. Furthermore, good agreement with numerical simulation is achieved. 相似文献
The high-resolution Fourier transform infrared spectrum of phosphorus trifluoride (PF3) has been reinvestigated in the v2?=?1 vibrational excited state near 487?cm?1 (at a resolution of 3?×?10–3?cm–1). Thanks to our new accurate rotational ground-state C0 value, 0.159970436(69)?cm–1, and to recent pure rotational measurements, 318 new infrared transitions of the ν2 fundamental band have been assigned, extending the rotational quantum number values up to Kmax?=?71 and Jmax?=?72. A merge, for the first time, of 135 reported microwave data (Kmax?=?42 and Jmax?=?49) within the v2?=?1 excited level and 2860 rovibrational transitions yielded improved constants of ν2. Parameters of this band have been obtained, up to sextic centrifugal distortion constants, by least-squares fits, σIR?=?3.60?×?10–4?cm–1 and σMW?=?5.53?×?10–6?cm–1 (166?kHz). Comparison of these constants with those measured previously by infrared spectroscopy reveals orders of magnitude higher accuracy of these new values. 相似文献
Laterally coupled quantum dot molecules (QDMs) were grown by molecular beam epitaxy. We describe the challenging growth process as well as morphological studies of the produced samples leading to a promising theoretical approach to describe the properties of the QDMs using a many‐body pseudopotential approach. Extensive spectroscopic measurements on these laterally coupled QDMs were performed. We prove the single quantum system nature of the considered QDMs by photon‐correlation measurements and analyze the photoluminescence (PL) and photoluminescence excitation (PLE) spectra under different aspects. The spectroscopic results are compared in detail to the performed theoretical calculations. Agreement between experiment and theory are presented, as well as, limitations of the model as indicated by most recent measurements.