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51.
52.
ABSTRACTSulfur monoxide radical has widely been detected in outer space using ground-state spectroscopy. The a 1Δ2 and b 1Σ+0+ states of this radical have low excitation energies, and they possibly exist in outer space. In this work, the potential energy curves and dipole moment functions of the two states were evaluated using the complete active space self- consistent field method, followed by the valence internally contracted multireference configuration interaction approach. The transition line positions, oscillator strengths, band transition dipole matrix elements, Einstein A coefficients, and Franck–Condon factors of all transitions were calculated for lower vibrational levels at rotational angular momentum quantum number J up to 150. The transition line positions calculated in this study are in good agreement with the experimental results. The rovibrational transition became noticeably weak at Δυ > 5. Comparing the results of a 1Δ2 and b 1Σ+0+ states reported in this paper with the previous values, we conclude that these results are the most accurate and complete to date. 相似文献
53.
ABSTRACTThis study computes the potential energy curves of the X1Σ+, A1Π, B1Δ, C1Σ+, and D1Π states of AlO+ cation and the transition dipole moments between them. The orders of the rotationless radiative lifetimes are 10–100?μs for the A1Π state, 1–1000?ms for the B1Δ state, 10?ns for the first well and 100?ns for the second well of the C1Σ+ state, and 1?μs for the D1Π state. Emissions of the B1Δ–A1Π and D1Π–C1Σ+ systems are so weak that they are hardly measured via spectroscopy, the emissions of the C1Σ+–X1Σ+, C1Σ+–A1Π, and D1Π–X1Σ+ systems are so strong that they can be detected readily, and emissions of the A1Π–X1Σ+ and D1Π–A1Π systems can be observed through spectroscopy only by a significant effort. There is a strong great similarity between spontaneous emissions of the A1Π–X1Σ+ system of the AlO+ cation and the A2Π–X2Σ+ system of the AlO radical. The emissions of the A2Π–X2Σ+ system of the AlO radical have been measured in outer space Therefore, it is highly possible that the emissions of the A1Π–X1Σ+ system of the AlO+ cation can be detected in the astrophysical media. 相似文献
54.
The potential energy curves for the X1∑ g, B1△g and B′1∑ g states of C2 have been studied by using MRCI and approximate CI methods, and are benchmarked against the calculations of full configuration interaction (FCI). The results obtained by MRCI method agree with the FCI very well, and even are accurate enough to compare other approximate methods as benchmark, when the calculations of FCI are not feasible. The approximate CI methods mentioned in this paper are reliable for treating chemical problems. 相似文献
55.
Solid-state nanopore in analytical chemistry has developed rapidly in the 1990s and it is proved to be a versatile new tool for bioanalytical chemistry. This review focuses on the analysis of ions and small molecules with nanopores including nanopipettes, polymer film nanopores, Si3N4 nanopores, graphene nanopores, MoS2 nanopores and MOFs. 相似文献
56.
可人工编程设计的刚性DNA分子瓦(DNA tile)中的DX分子(double-crossover,双交叉)能自组装形成二维DNA晶体。将含有二维DNA晶体的缓冲溶液程序升温,用紫外-可见分光光度计在260 nm处测定二维DNA晶体的熔解曲线,观测到了DNA晶体的多重熔解过程。AFM显微镜的研究也观测到了二维DNA晶体受热解体后的图像,表明二维DNA晶体的熔解过程首先发生在DX分子瓦间的黏性末端,然后是DX分子瓦的解体,由此推测,在DNA晶体生长过程中单链DNA相互结合成分子瓦后,分子瓦进一步自组装成晶体。 相似文献
57.
In this paper the values of the crystalline-electric-field
parameters Anm for R2Fe17 and
R2Fe17H3 (R=Tb,Ho,Er) are evaluated by fitting
calculations to the magnetization curves measured on the single
crystal at several temperatures. The fitted Anm for
R2Fe17 are strikingly different from those for the
corresponding R2Fe17H3. The energy gaps between the
lowest four energy levels for Ho ions in Ho2Fe172 can be
reproduced by using the fitted Anm and exchange field
2μBHex, which estimated from the fit of the
temperature dependence of the spontaneous magnetization combined
with inelastic neutron scattering experiment. 相似文献
58.
59.
60.
本文研究了~(40)Ca~(35)Cl分子低态的自旋轨道耦合分裂以及获得更精确的光谱常数和更高的激发态.以从头算理论为基础,使用多参考组态相互作用方法获得了该分子的势能曲线和自旋轨道分裂,之后求解径向一维薛定谔方程获得光谱常数.得到了~(40)Ca~(35)Cl分子7个Λ-S低电子态的势能曲线和永久偶极矩,以及A~2Π→~2Σ~+,1~2Δ和C~2Π→~2Σ~+,1~2Δ跃迁的跃迁偶极矩,得到的光谱常数(不管是考虑了自旋轨道耦合(SOC)还是没有考虑SOC)与实验值非常符合,且要好于之前的理论计算结果 .值得注意的是,目前的计算还首次得到了C~2Π→~2Σ+,1~2Δ跃迁的跃迁性质,为之后实验观察~(40)Ca~(35)Cl分子的高激发态光谱和跃迁性质提供有益的理论参考. 相似文献