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2.
Based on the tunable intensity and waist of Gaussian laser, harmonic-like and toroidal potentials can be achieved and the ground-state properties of the dipolar Bose–Einstein condensate (BEC) trapped in such potentials are investigated. It is found that, in the harmonic-like potential, the singly and doubly quantized vortices can exist in the scale condensate and translate respectively into vortex pairs and triangular vortex lattice with increasing dipole–dipole interaction (DDI). Especially, the sandwich-like structure can be observed in the ground-state density profiles by tuning the direction and strength of DDI for some rotating frequency. In the toroidal potential, the competition between the inter-component interaction and DDI can induce the transition between immiscible and miscible states, and results in the structures of a doubly quantized vortex surrounded by a vortex ring. It is worth emphasizing that, with the increasing of DDI, the doubly quantized vortex in the harmonic-like potential becomes two singly quantized vortices, while in the toroidal potential it is no happen due to the presence of Gaussian barrier.  相似文献   
3.
采用电磁场有限元方法,数值模拟了孔径型扫描近场光学显微镜(aperture Scanning Near-field Optical Microscopy,a-SNOM)在照明模式下的工作过程.针对金偶极天线结构,改变天线长度和纳米间隙尺寸,计算了a-SNOM探针孔径的远场辐射速率随探针端面中心坐标变化的扫描曲线,实现了超越a-SNOM探针通光孔径尺寸的天线金属纳米间隙的超分辨测量,对于100nm通光孔径的探针,可分辨最小尺寸为10nm(0.016倍波长)的金属间隙.通过对比金属和介质偶极天线的a-SNOM探针远场辐射速率测量的计算结果,表明天线金属纳米间隙的超分辨测量的实现是由于金属间隙表面等离激元的激发.  相似文献   
4.
《印度化学会志》2022,99(11):100767
The optimized geometric parameters of the 2-Amino-6-chlorofluoren-9-one (2A6CF9O) compound were estimated by employing density functional theory. The electronic characteristics of the molecule were explored using molecular frontier orbital energies and the MEP surface. Kamlet's and Catalan's multiple linear regression techniques along with different polarity functions were used to investigate the influence of pure solvents on spectral properties. In the system, both general solute-solvent and hydrogen bonding interactions are active. However, as compared to normal solute-solvent interactions, hydrogen bonding interactions have a smaller role. In addition, using computed ground state dipole moment, solvatochromic correlations were employed to infer excited state dipole moment.  相似文献   
5.
Abstract

The highly polarizable perovskite-type oxide, KTaO3 doped simultaneously with Li+ and Nb5+ (K1?xLixTa1?yNbyO3, KLTN), reveals unexpected properties and ordering effects. Studies of the dielectric permittivity ?'(T, f) (10—300K, 100Hz-1 MHz) for x = 0.0014 and y = 0.024 show collective dipolar ordering effects with a transition from paraelectric into a mixed phase (coexisting dipole-glass-like and long-range ordered ferroelectric phases) taking place near 39 K. At 15 K another phase transition into a reentrant dipolar glass-like state is observed. Such a sequence of transitions and the existence of a reentrant glass state are unknown for electrical dipolar systems.  相似文献   
6.
Abstract

Recently very encouraging results of semiempirical parameteric calculation of dipole transition moments of the lowest energy t1 ? 2e (1A1 - 1T2) transition of permanganate and chromate ions have been reported. In the case of vanadate ion, which is isoelectronic with the permanganate and chromate ion, no such study of spectral intensities appears to have been reported so far. A parameteric calculation in terms of a single parameter β, the ligand mixing coefficient using Richardson's orbitals4 and both dipole velocity and dipole length operators have been reported in the present paper.  相似文献   
7.
利用密度泛函理论(DFT)在B3LYP/6-311G++(d,p)水平上对溴化苄分子进行了结构优化和频率计算,得到了该分子的稳定构型和全部振动模式。计算得到的几何参数通过与苯分子的实验值相比,发现理论值与其相吻合;理论计算和实验测得的红外光谱数据的比较分析表明,理论计算与实验测量结果符合得较好,并对其振动模式进行了归属。最后,在B3LYP/6-311G++(d,p)水平上计算得到了溴化苄阳离子的红外光谱,并与溴化苄进行了比较,计算表明电离对振动偶极距产生了较大影响。  相似文献   
8.
High dielectric loss materials have an important application in electromagnetic (EM) absorption fields. In this paper, the ternary nanocomposites: 1T/2H-MoS2/Mo2S3 with heterogeneous interfaces are synthesized by hydrothermal method. XRD, XPS, FTIR, SEM, and TEM measurements are applied to study the structure, morphology, and composition. The frequency spectra of complex permittivity (εr-f) are measured in 2–18 GHz by vector network analyzer. The results show that the nanocomposites have higher dielectric loss angle tangents than the reported 2H-MoS2 absorbers. Based on the εr-f spectra, the reflection loss-frequency curves (RLf) are simulated at given thicknesses. An effective absorption bandwidth of 5.2 GHz (12.8–18 GHz) and a RL peak of −29.49 dB are achieved in a thin thickness of 1.62 mm, which are comparable to the reported 2H-MoS2 absorbers with complex composition, showing that the 1T/2H-MoS2/Mo2S3 nanocomposites have great application potential as an EM wave absorber in the Ku band.  相似文献   
9.
We consider the quantum and classical dissociation dynamics of heteronuclear diatomic molecules induced by infrared laser pulses. The field–molecule interaction is given by the product of the time-dependent electric field and the molecule permanent dipole. We investigate the influence of the dipole function in molecular dissociation. We show that the dissociation can be suppressed at certain external field frequencies for a nonlinear and finite-range dipole function. The correspondence between quantum and classical results is established by relating classical Fourier amplitudes to discrete–continuum quantum matrix elements.  相似文献   
10.
A Charge density analysis of CTB molecule in gas phase (Form I ) and the same present at the active site (Form II ) of p300 enzyme were performed for the wave functions obtained from the Density functional method (B3LYP) with the basis set 6‐311G**. This study has been carried out to understand the nature of conformational modification, charge redistribution and the change of electrostatic moments of the CTB molecule when present at the active site of p300. The difference of charge density distribution between both forms of CTB molecule explicitly indicates the effect of intermolecular interaction on CTB molecule in the active site. The dipole moment of CTB in the gas phase (9.6 D) has been significantly decreased (4.27 D) when it present at the active site of p300; this large variation is attributed to the charge redistribution in CTB, due to the intermolecular interaction between the CTB and the receptor p300 molecule. The electrostatic potential maps differentiate the difference of electrostatic potential between the two forms. A large electronegative region is found at the vicinity of oxygen and fluorine atoms. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2012  相似文献   
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