Hyper Raman spectra calculated in a time-dependent Hartree–Fock method

Hyper Raman scattering (HRS) of the benzonitrile (BN) and 1,3,5-trinitro-1,3,5-triazacyclohexane (RDX) molecules is studied by means of ab initio calculations. The computational procedure employs a recently developed methodology for the analytic calculations of frequency-dependent polarizability gradients of arbitrary order, including perturbation dependent basis sets. The result are compared to normal Raman scattering (NRS) and coherent anti-Stokes Raman scattering (CARS) that previously have been studied using the same technology. It is found that some suppressed or silent modes in CARS and NRS spectra are clearly seen in HRS, and that although under general excitation conditions the HRS intensities are much lower than for CARS and NRS, HRS provides complementary information useful for target identification.     

Steric effect is a decisive factor on the orientation preference of guest into host: evidence from 5-indanol/β-CD model

The present study evidences the role of steric effect in the orientation preference of guest into host using the 1:1 inclusion complex of 5-indanol/β-CD model. Two different orientations of guest (5-indanol) into host (β-CD) are considered for the inclusion of 5-indanol into the cavity through the 2° rim of β-CD. The energy differences in the inclusion process are calculated using PM3 semi-empirical method and HF/6-31G^** basis set. By the investigation of stabilisation energies, it is found that the energy of both orientations increases to maximum value due to the increase of steric repulsive effect when the crowding of bulky group of 5-indanol occurs at 1° or 2° rim of β-CD. On comparing the fluorescence spectral data of 5-indanol:β-CD complex and 2-napthol:β-CD complex, it is observed that the steric effect is intensified due to the presence of bulky group.     

Entangling Lattice-Trapped Bosons with a Free Impurity: Impact on Stationary and Dynamical Properties

We address the interplay of few lattice trapped bosons interacting with an impurity atom in a box potential. For the ground state, a classification is performed based on the fidelity allowing to quantify the susceptibility of the composite system to structural changes due to the intercomponent coupling. We analyze the overall response at the many-body level and contrast it to the single-particle level. By inspecting different entropy measures we capture the degree of entanglement and intraspecies correlations for a wide range of intra- and intercomponent interactions and lattice depths. We also spatially resolve the imprint of the entanglement on the one- and two-body density distributions showcasing that it accelerates the phase separation process or acts against spatial localization for repulsive and attractive intercomponent interactions, respectively. The many-body effects on the tunneling dynamics of the individual components, resulting from their counterflow, are also discussed. The tunneling period of the impurity is very sensitive to the value of the impurity-medium coupling due to its effective dressing by the few-body medium. Our work provides implications for engineering localized structures in correlated impurity settings using species selective optical potentials.     

核势和核子有效质量的同位旋相关性

在Dirac Brueckner Hartree-Fock (DBHF)理论框架下研究了核子光学势和核子有效质量的同位旋相关性. 非对称核物质的计算采用了DBHF的核子自能的Dirac结构的新的分解方法, 核子自能的实部是用G矩阵在Hartree-Fock近似下计算得到, 而虚部从极化图得到. 用核子的薛定谔等价势可以得到核子矢量有效质量. 研究表明考虑了核势的能量相关性在丰中子核物质情况下核子矢量有效质量比质子的大.     

Nonlinear Hartree equation in high energy-mass

This paper is concerned with the Cauchy problem of the nonlinear Hartree equation. By constructing a constrained variational problem, we get a refined Gagliardo–Nirenberg inequality and the best constant for this inequality. We thus derive two conclusions. Firstly, by establishing and analyzing the invariant manifolds, we obtain a new criteria for global existence and blowup of the solutions. Secondly, we get other sufficient condition for global existence with the discussing of the Bootstrap argument. And based on these two conclusions, we also deduce so-called energy-mass control maps, which expose the relationship between the initial data and the solutions.     

Preconditioned gradient flows for nonlinear eigenvalue problems and application to the Hartree‐Fock functional

In this article, we propose to solve numerically the problem of finding the smallest eigenvalues of a Hermitian operator (and the space spanned by the corresponding eigenvectors) by a gradient flow technique. This method is then applied to the Hartree‐Fock problem. Improvements are also proposed in two directions: preconditioning of the dynamical system and development of a specific flow that enables to compute directly the eigenvectors. © 2008 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2009     

FT‐IR,FT‐Raman and SERS spectra of anilinium sulfate

The FT‐IR and FT‐Raman spectra of anilinium sulfate were recorded and analyzed. The surface‐enhanced Raman scattering (SERS) was recorded from a silver electrode. The vibrational wavenumbers of the compound have been computed using the Hartree‐Fock/6‐31G* basis and compared with the experimental values. The molecule is adsorbed on the silver surface with the benzene ring in a tilted orientation. The presence of amino and sulfate group vibrations in the SERS spectrum reveal the interaction between amino and sulfate groups with the silver surface. The direction of the charge transfer contribution to SERS has been discussed from the frontier orbital theory. Copyright © 2009 John Wiley & Sons, Ltd.     

系统-热库模型平衡约化密度矩阵的精确计算:多层多构型含时Hartree方法及其与多电子态路径积分分子动力学方法的比较

An efficient and accurate method for computing the equilibrium reduced density matrix is presented for treating open quantum systems characterized by the system-bath model. The method employs the multilayer multiconfiguration time-dependent Hartree theory for imaginary time propagation and an importance sampling procedure for calculating the quantum mechanical trace. The method is applied to the spin-boson Hamiltonian, which leads to accurate results in agreement with those produced by the multi-electronic-state path integral molecular dynamics method.     

蒽醌衍生物的三阶非线性光学极化率

用有限场 (FF)和含时间的耦合微扰 Hartree- Fork方法计算了蒽醌及其衍生物的三阶非线性光学 (NLO)极化率。计算表明 ,2 ,6位双取代物具有较大的响应系数 ,且随着取代基供电性的增强而增大。含频率的 NLO极化率大于静态值 ,且随频率的增大而增大。