The quantum phase effects for induced electric and magnetic dipole moments are investigated. It is shown that the phase shift received by the induced electric dipole has the same form as the one induced by magnetic di...The quantum phase effects for induced electric and magnetic dipole moments are investigated. It is shown that the phase shift received by the induced electric dipole has the same form as the one induced by magnetic dipole moment, therefore the total phase is a hybrid of these two types of phase. This feature indicates that to have a decisive measurement on either one of these two phases, it is necessary to measure the velocity dependence of the observed phase.展开更多
The single-particle Schrödinger fluid model is designed mainly to calculate the moments of inertia of the axially symmetric deformed nuclei by assuming that each nucleon in the nucleus is moving in a single-parti...The single-particle Schrödinger fluid model is designed mainly to calculate the moments of inertia of the axially symmetric deformed nuclei by assuming that each nucleon in the nucleus is moving in a single-particle potential which is deformed with time t, through its parametric dependence on a classical shape variable α(t). Also, the Nilsson model is designed for the calculations of the single-particle energy levels, the magnetic dipole moments, and the electric quadrupole moments of axially symmetric deformed nuclei by assuming that all the nucleons are moving in the field of an anisotropic oscillator potential. On the other hand, the nuclear superfluidity model is designed for the calculations of the nuclear moments of inertia and the electric quadrupole moments of deformed nuclei which have no axes of symmetry by assuming that the nucleons are moving in a quadruple deformed potential. Furthermore, the cranked Nilsson model is designed for the calculations of the total nuclear energy and the quadrupole moments of deformed nuclei which have no axes of symmetry by modifying the Nilsson potential to include second and fourth order oscillations. Accordingly, to investigate whether the six p-shell isotopes <sup>6</sup>Li, <sup>7</sup>Li, <sup>8</sup>Li, <sup>9</sup>Li, <sup>10</sup>Li, and <sup>11</sup>Li have axes of symmetry or not, we applied the four mentioned models to each nucleus by calculating their moments of inertia, their magnetic dipole moments, and their electric quadrupole moments by varying the deformation parameter β and the non-axiality parameter γ in wide ranges of values for this reason. Hence for the assumption that these isotopes are deformed and have axes of symmetry, we applied the single-particle Schrödinger fluid model and the Nilsson model. On the other hand, for the assumption that these isotopes are deformed and have no axes of symmetry, we applied the cranked Nilsson model and the nuclear super fluidity model. As a result of our calculations, we can conclude that the nucleus <sup>6</sup>Li may be assumed to be deformed and has an axis of symmetry.展开更多
An ab initio calculations on the ground and low-lying excited statesX2∑+,2^2∑+,3^2∑+,1^4∏,2^4∏,1^4∑+,2^4∑+,and 3^4∑+of KBe molecule have been performed using multireference configuration interaction (M...An ab initio calculations on the ground and low-lying excited statesX2∑+,2^2∑+,3^2∑+,1^4∏,2^4∏,1^4∑+,2^4∑+,and 3^4∑+of KBe molecule have been performed using multireference configuration interaction (MRCI) plus Davidsoncorrections (MRCI+Q) approach with all electron basis set aug-cc-pCV5Z-DK for Be and def2-AQZVPP-JKFI for K.3^2∑+,1^4∏,2^4∏,1^4∑+,2^4∑+and3^4∑+states are investigated for the first time. Inner shell electron correlations are computed on the potential energy curves (PECs) calculations. The spectroscopic and molecular parameters are also predicted. In addition, The transition properties including transition dipole moment, Franck-Condon factors qv′v″, Einstein coefficients Av′v″, and the radiative lifetimesτ′for the2^2∑+-X2∑+,3^2∑+-X2∑+,and 2^4∏-1^4∏ transitions are predictedat the same time.展开更多
Recently, the diverse properties of Rydberg atoms, which probably arise from its large electric dipole moment (EDM), have been explored. In this paper, we report electric dipole moments along with Stark energies and...Recently, the diverse properties of Rydberg atoms, which probably arise from its large electric dipole moment (EDM), have been explored. In this paper, we report electric dipole moments along with Stark energies and charge densities of lithium Rydberg states in the presence of electric fields, calculated by matrix diagonalization. Huge electric dipole moments are discovered. In order to check the validity of the EDMs, we also use these electric dipole moments to calculate the Stark energies by numerical integration. The results agree with those calculated by matrix diagonalization.展开更多
The coherent exciton plays an important role in the photosynthetic primary process, and its functions are deeply dependent on the orientation arrangements of local transition dipole moments (TDMs). We theoretically ...The coherent exciton plays an important role in the photosynthetic primary process, and its functions are deeply dependent on the orientation arrangements of local transition dipole moments (TDMs). We theoretically and systematically study the physical property of the coherent exciton at different orientation arrangements of the local TDMs in circular light-harvesting (LH) complexes. Especially, if the orientation arrangements are different, the delocalized TDMs of the coherent excitons and the energy locations of the optically active coherent excitons (OACEs) can be obviously different, and then there are more manners to capture, store and transfer light energy in and between LH complexes. Similarly, if the orientation arrangements are altered, light absorption and radiative intensities can be converted fully between the OACEs in the upper and lower coherent exciton bands, and then the blue and red shifts of the absorption and radiative bands of the pigment molecules can occur simultaneously at some orientation arrangements. If the systems are in the vicinities of the critical orientation arrangements, the weak static disorder or small thermal excitation can destroy the coherent electronic excitations, and then the coherent exciton cannot exist any more.展开更多
Many of the technology and computational chemistry applications are used to study drugs and their biological effects. Flutab®drug contains Paracetamol, Diphenhydramine and Pseudoephedrine. Ab-initio calculatio...Many of the technology and computational chemistry applications are used to study drugs and their biological effects. Flutab®drug contains Paracetamol, Diphenhydramine and Pseudoephedrine. Ab-initio calculations were performed at DFT/B3LYP and HF methods with three basis sets, namely, STO-3G, 3-21G, and 6-31G(d) in order to calculate the dipole moments of the three constituents of Flutab®drug. The Diphenhydramine compound was found to be the most stable constituent, with the lowest value of dipole moment.展开更多
The anomalous magnetic(MDM)and electric(EDM)dipole moments of theτlepton serve as crucial indicators of new physics beyond the standard model.Leveraging azimuthal angular asymmetry as a novel tool in ultraperipheral ...The anomalous magnetic(MDM)and electric(EDM)dipole moments of theτlepton serve as crucial indicators of new physics beyond the standard model.Leveraging azimuthal angular asymmetry as a novel tool in ultraperipheral collisions(UPCs),we attain unparalleled precision in the study of these key properties.Driven by the highly linear polarization of coherent photons,this method uniquely enables both the MDM and EDM to contribute to the cos 2φangular distribution in similar magnitudes.Importantly,our approach substantially narrows the parameter space,excluding more than half of it compared to expected UPC-based measurements reliant solely on the total cross-section.This method not only provides improved constraints but also minimizes the need for additional theoretical assumptions,and offers a novel avenue to probe the EDM effects.展开更多
Propagation of a few-cycle laser pulses in a dense V-type three-level atomic medium is investigated based on full-wave Maxwell-Bloch equations by taking the near dipole-dipole (NDD) interaction into account. We find...Propagation of a few-cycle laser pulses in a dense V-type three-level atomic medium is investigated based on full-wave Maxwell-Bloch equations by taking the near dipole-dipole (NDD) interaction into account. We find that the ratio, γ of the transition dipole moments has strong influence on the time evolution and split of the pulse: when γ≤ 1, the NDD interaction delays propagation and split of the pulse, and this phenomenon is more obvious when the value of γ is smaller; when γ =√2, the NDD interaction accelerates propagation and split of the pulse.展开更多
We systematically study the magnetic dipole moments of multiquark states.In this study,the magnetic dipole moments of possible B^(−)B^(∗−),B^(0)B^(∗−),B^(−)B^(∗0),B^(0)B^(∗0),B_(s)^(0)B^(∗−),B_(−)B_(s)^(∗0),B_(s)^(0)B...We systematically study the magnetic dipole moments of multiquark states.In this study,the magnetic dipole moments of possible B^(−)B^(∗−),B^(0)B^(∗−),B^(−)B^(∗0),B^(0)B^(∗0),B_(s)^(0)B^(∗−),B_(−)B_(s)^(∗0),B_(s)^(0)B^(∗0),B^(0)B_(s)^(∗0),and B_(s)^(0)B_(s)^(∗0) states are extracted using light-cone sum rules.We explore the magnetic dipole moments of these states in a molecular picture with spin-parity JP=1^(+).The magnetic dipole moments of hadrons include useful information on the distributions of internal charge and magnetization,which can be used to understand their geometrical shapes and quark-gluon organization.The results of the present study along with the spectroscopic parameters may help future theoretical and experimental research on the characteristics of doubly-bottom tetraquark states.展开更多
Stretching vibrational band intensities of XH3 (X=N, Sb) molecules are investigated employing three-dimensional dipole moment surfaces combined with the local mode Hamiltonian model. The dipole moment surfaces of NH...Stretching vibrational band intensities of XH3 (X=N, Sb) molecules are investigated employing three-dimensional dipole moment surfaces combined with the local mode Hamiltonian model. The dipole moment surfaces of NH3 and SbH3 are calculated with the density functional theory and at the correlated MP2 level, respectively. The calculated band intensities are in good agreement with the available experimental data. The contribution to the band intensities from the different terms in the polynomial expansion of the dipole moments of four group V hydrides (NH3, PH3, AsH3 and SbH3) are discussed. It is concluded that the breakdown of the bond dipole approximation must be considered. The intensity “borrowing” effect due to the wave function mixing among the stretching vibrational states is found to be less significant for the molecules that reach the local mode limit.展开更多
The reasonable dissociation limit of the A^1∑+ state ^7LiH molecule is obtained. The accurate dissociation energy and the equilibrium geometry of this state are calculated using a symmetry-adapted-cluster configurat...The reasonable dissociation limit of the A^1∑+ state ^7LiH molecule is obtained. The accurate dissociation energy and the equilibrium geometry of this state are calculated using a symmetry-adapted-cluster configuration-interaction method in complete active space for the first time, The whole potential energy curve and the dipole moment function for the A^1∑+ state are calculated over a wide internuclear separation range from about 0.1 to 1.4 nm. The calculated equilibrium geometry and dissociation energy of this potential energy curve are of Re=0.2487 nm and De=1.064eV, respectively. The unusual negative values of the anharmonicity constant and the vibration-rotational coupling constant are of ωeXe=-4.7158cm^-1 and αe=0.08649cm^-1, respectively. The vertical excitation energy from the ground to the A^1∑+ state is calculated and the value is of 3.613eV at 0.15875nm (the equilibrium position of the ground state). The highly anomalous shape of this potential energy curve, which is exceptionally flat over a wide radial range around the equilibrium position, is discussed in detail. The harmonic frequency value of 502.47cm^-1 about this state is approximately estimated. Careful comparison of the theoretical determinations with those obtained by previous theories about the A^1∑+ state dissociation energy clearly shows that the present calculations are much closer to the experiments than previous theories, thus represents an improvement.展开更多
Dielectrophoresis (DEP) is one of the most popular techniques for bio-particle manipulation in microfluidic systems. Traditional calculation of dielectrophoretic forces of single particle based on the approximation ...Dielectrophoresis (DEP) is one of the most popular techniques for bio-particle manipulation in microfluidic systems. Traditional calculation of dielectrophoretic forces of single particle based on the approximation of equivalent dipole moment (EDM) cannot be directly applied on the dense particle interactions in an electrical field. The Maxwell stress tensor (MST) method is strictly accurate in the theory for dielectrophoretic forces of particle interaction, but the cumbersome and complicated numerical computation greatly limits its practical applications. A novel iterative dipole moment (IDM) method is pre- sented in this work for calculating the dielectrophoretic forces of particle-particle inter- actions. The accuracy, convergence, and simplicity of the IDM are confirmed by a series of examples of two-particle interaction in a DC/AC electrical field. The results indicate that the IDM is able to calculate the DEP particle interaction forces in good agreement with the MST method. The IDM is a purely analytical operation and does not require complicated numerical computation for solving the differential equations of an electrical field while the particle is moving.展开更多
Single-crystal X-ray diffraction structural data of four Fe-Mg tourmalines with different Fe contents from Xinjiang, Sichuan, and Yunnan Provinces, China, were collected at room temperature and-100oC. The intrinsic di...Single-crystal X-ray diffraction structural data of four Fe-Mg tourmalines with different Fe contents from Xinjiang, Sichuan, and Yunnan Provinces, China, were collected at room temperature and-100oC. The intrinsic dipole moments of polyhedra and the total intrinsic dipole moment of the unit cell were calculated. By comparing the intrinsic electric dipole moments of the X, Y, Z, T, and B site polyhedra, it is found that the T site polyhedron makes the greatest contribution to the total intrinsic dipole moment. The pyroelectric coefficients of four Fe-Mg tourmalines were experimentally determined, and the influence of intrinsic dipole moments on their pyroelectric properties was inves-tigated. The experimental results show that, compared with the case at room temperature, the intrinsic dipole moments change with the total Fe content at-100oC in a completely different way. With the decrease of temperature, the total intrinsic dipole moments of tourmaline de-crease. Over the same temperature interval, the pyroelectric coefficients increase with the increase in intrinsic dipole moment.展开更多
The mean-square radius of gyration <S^2>,the mean-square dipole moment <D^2>,the mean-square end-to-end distance <R^2> and their temperature coefficients of unsymmetrical disubstituted poly(methylphe...The mean-square radius of gyration <S^2>,the mean-square dipole moment <D^2>,the mean-square end-to-end distance <R^2> and their temperature coefficients of unsymmetrical disubstituted poly(methylphenylsiloxane) (PMPS) chains, as a function of stereochemical structure,confomational energies and length of polymers,were studied by using an improved configurational-confomational statistical method based on the rotational-isomeric-state theory.It is found that the increase in isotacticity of P...展开更多
Steady-state absorption and fluorescence spectra, and time-resolved fluorescence spectra of coumarin 343 (C343) were measured in different solvents. The effect of the solvent on the spectral properties and dipole mo...Steady-state absorption and fluorescence spectra, and time-resolved fluorescence spectra of coumarin 343 (C343) were measured in different solvents. The effect of the solvent on the spectral properties and dipole moment of the lowest excited state of C343 were investigated. It was found that the absorption and fluorescence spectra red-shifted slightly and strongly with increasing solvent polarity, respectively, because the charge distribution of the excited state leaded to the increasing difference between the absorption and fluorescence spectra with increasing solvent polarity. The dipole moment of the lowest excited state of C343 was determined from solvatochromic measurements and the quantum chemical calculation, and the results obtained from these two methods were fully consistent. Investigations of the time-resolved fluorescence of C343 in different solvents indicated that the fluorescence lifetimes increased nearly linearly with 4.45 ns in water. This can be ascribed between C343 and hydrogen donating increasing solvent polarity from 3.09 ns in toluene to to the intermolecular hydrogen bonding interactions solvents展开更多
An accurate electric dipole moment function(EDMF) is obtained for the carbon monoxide(CO) molecule(X1+Σ)by fitting the experimental rovibrational transitional moments. Additionally, an accurate ab initio EDMF is foun...An accurate electric dipole moment function(EDMF) is obtained for the carbon monoxide(CO) molecule(X1+Σ)by fitting the experimental rovibrational transitional moments. Additionally, an accurate ab initio EDMF is found using the highly accurate, multi-reference averaged coupled-pair functional(ACPF) approach with the basis set, aug-cc-p V6 Z, and a finite-field with ±0.005 a.u.(The unit a.u. is the abbreviation of atomic unit). This ab initio EDMF is very consistent with the fitted ones. The vibrational transition matrix moments and the Herman–Wallis factors, calculated with the Rydberg–Klein–Rees(RKR) potential and the fitted and ab initio EDMFs, are compared with experimental measurements. The consistency of these line intensities with the high-resolution transmission(HITRAN) molecular database demonstrates the improved accuracy of the fitted and ab initio EDMFs derived in this work.展开更多
A dressed-state perturbation theory beyond the rotating wave approximation (RWA) is presented to investigate the interaction between a two-level electronic transition of polar molecules and a quantized cavity field....A dressed-state perturbation theory beyond the rotating wave approximation (RWA) is presented to investigate the interaction between a two-level electronic transition of polar molecules and a quantized cavity field. Analytical expressions can be explicitly derived for both the ground- and excited-state-energy spectrums and wave functions of the system, where the contribution of permanent dipole moments (PDM) and the counter-rotating wave term (CRT) can be shown separately. The validity of these explicit results is discussed by comparison with the direct numerical simulation. Compared to the CRT coupling, PDM results in the coupling of more dressed states and the energy shift is proportional to the square of the normalized permanent dipole difference, and a greater Bloch-Siegert shift can be produced in the giant dipole molecule cavity QED. In addition, our method can also be extended to the solution of the two-level atom Rabi model Hamiltonian beyond the RWA.展开更多
Recently,more attention have been paid on the construction of dipole moment functions(DMF)using theoretical methods.However,the computational methods to construct DMFs are not validated as much as those for potential ...Recently,more attention have been paid on the construction of dipole moment functions(DMF)using theoretical methods.However,the computational methods to construct DMFs are not validated as much as those for potential energy surfaces do.In this letter,using Ar…He as an example,we tested how spectroscopyaccuracy DMFs can be constructed using ab initio methods.We especially focused on the basis set dependency in this scenario,i.e.,the convergence of DMF with the sizes of basis sets,basis set superposition error,and mid-bond functions.We also tested the explicitly correlated method,which converges with smaller basis sets than the conventional methods do.This work can serve as a pictorial sample of all these computational technologies behaving in the context of constructing DMFs.展开更多
We report a sensitive detection of high Rydberg atom with large dipole moment utilizing its deflection near a pair of parallel cylindrical copper rods which are oppositely charged. When the low-field seeking state Ryd...We report a sensitive detection of high Rydberg atom with large dipole moment utilizing its deflection near a pair of parallel cylindrical copper rods which are oppositely charged. When the low-field seeking state Rydberg atoms fly across the gradient electric field formed by the pair of rods, they will be pushed away from the rods while the high-field seeking state ones will be attracted towards the rods. These atoms will form different patterns on an ion imaging system placed downwards at the end of the rods. The spatial distribution of the deflected atoms on the imaging system is also simulated, in good agreement with the experimental results, from which we can deduce the quantum state information of the excited atoms. This state resolvable Rydberg atom detection can be used for the dynamics research of the dipole-dipole interaction between atoms with large dipole moments.展开更多
The transition dipole moments(TDMs) of ultracold85 Rb133 Cs molecules between the lowest vibrational ground level, (X^1Σ~+( v= 0, J= 1), and the two excited rovibrational levels, 2~3Π0+(v′= 10, J′= 2) and...The transition dipole moments(TDMs) of ultracold85 Rb133 Cs molecules between the lowest vibrational ground level, (X^1Σ~+( v= 0, J= 1), and the two excited rovibrational levels, 2~3Π0+(v′= 10, J′= 2) and 2~1Π1(v′= 22,J′= 2), are measured using depletion spectroscopy. The ground-state85 Rb133 Cs molecules are formed from cold mixed component atoms via the 2~3Π0-( v= 11, J= 0) short-range level, then detected by time-of-flight mass spectrum. A home-made external-cavity diode laser is used as the depletion laser to couple the ground level and the two excited levels. Based on the depletion spectroscopy, the corresponding TDMs are then derived to be 3.5(2)×10^(-3)eαα and 1.6(1)×10^(-2)eαα, respectively, where 0)(60 represents the atomic unit of electric dipole moment. The enhance of TDM with nearly a factor of 5 for the 21Π1(v′= 22, J′= 2) excited level means that it has stronger coupling with the ground level. It is meaningful to find more levels with much more strong coupling strength by the represented depletion spectroscopy to realize direct stimulated Raman adiabatic passage transfer from scattering atomic states to deeply molecular states.展开更多
基金Supported by the China Scholarship Councilthe Hanjiang Scholar Project of Shaanxi University of Technology
文摘The quantum phase effects for induced electric and magnetic dipole moments are investigated. It is shown that the phase shift received by the induced electric dipole has the same form as the one induced by magnetic dipole moment, therefore the total phase is a hybrid of these two types of phase. This feature indicates that to have a decisive measurement on either one of these two phases, it is necessary to measure the velocity dependence of the observed phase.
文摘The single-particle Schrödinger fluid model is designed mainly to calculate the moments of inertia of the axially symmetric deformed nuclei by assuming that each nucleon in the nucleus is moving in a single-particle potential which is deformed with time t, through its parametric dependence on a classical shape variable α(t). Also, the Nilsson model is designed for the calculations of the single-particle energy levels, the magnetic dipole moments, and the electric quadrupole moments of axially symmetric deformed nuclei by assuming that all the nucleons are moving in the field of an anisotropic oscillator potential. On the other hand, the nuclear superfluidity model is designed for the calculations of the nuclear moments of inertia and the electric quadrupole moments of deformed nuclei which have no axes of symmetry by assuming that the nucleons are moving in a quadruple deformed potential. Furthermore, the cranked Nilsson model is designed for the calculations of the total nuclear energy and the quadrupole moments of deformed nuclei which have no axes of symmetry by modifying the Nilsson potential to include second and fourth order oscillations. Accordingly, to investigate whether the six p-shell isotopes <sup>6</sup>Li, <sup>7</sup>Li, <sup>8</sup>Li, <sup>9</sup>Li, <sup>10</sup>Li, and <sup>11</sup>Li have axes of symmetry or not, we applied the four mentioned models to each nucleus by calculating their moments of inertia, their magnetic dipole moments, and their electric quadrupole moments by varying the deformation parameter β and the non-axiality parameter γ in wide ranges of values for this reason. Hence for the assumption that these isotopes are deformed and have axes of symmetry, we applied the single-particle Schrödinger fluid model and the Nilsson model. On the other hand, for the assumption that these isotopes are deformed and have no axes of symmetry, we applied the cranked Nilsson model and the nuclear super fluidity model. As a result of our calculations, we can conclude that the nucleus <sup>6</sup>Li may be assumed to be deformed and has an axis of symmetry.
基金Project supported by the National Natural Science Foundation of China(Grant No.11647075)the Scientific Research Fund of Sichuan Provincial Education Department,China(Grant No.14ZB0284)the Scientific Research Key Project of Yibin University,China(Grant No.2013QD09)
文摘An ab initio calculations on the ground and low-lying excited statesX2∑+,2^2∑+,3^2∑+,1^4∏,2^4∏,1^4∑+,2^4∑+,and 3^4∑+of KBe molecule have been performed using multireference configuration interaction (MRCI) plus Davidsoncorrections (MRCI+Q) approach with all electron basis set aug-cc-pCV5Z-DK for Be and def2-AQZVPP-JKFI for K.3^2∑+,1^4∏,2^4∏,1^4∑+,2^4∑+and3^4∑+states are investigated for the first time. Inner shell electron correlations are computed on the potential energy curves (PECs) calculations. The spectroscopic and molecular parameters are also predicted. In addition, The transition properties including transition dipole moment, Franck-Condon factors qv′v″, Einstein coefficients Av′v″, and the radiative lifetimesτ′for the2^2∑+-X2∑+,3^2∑+-X2∑+,and 2^4∏-1^4∏ transitions are predictedat the same time.
基金supported by the National Basic Research Program of China(Grant No.2012CB921603)the National Natural Science Foundation of China(GrantNos.61378039,61078013,61178009,and 11274209)+3 种基金the Program for Changjiang Scholars and Innovative Research Team in University,China(Grant No.IRT13076)the Fund for Fostering Talents in Basic Science of the National Natural Science Foundation of China(Grant No.J1210036)the Natural Science Foundation of Shanxi Province,China(Grant No.2012011003-2)the Shanxi International Collaboration Program,China(Grant No.2010081046)
文摘Recently, the diverse properties of Rydberg atoms, which probably arise from its large electric dipole moment (EDM), have been explored. In this paper, we report electric dipole moments along with Stark energies and charge densities of lithium Rydberg states in the presence of electric fields, calculated by matrix diagonalization. Huge electric dipole moments are discovered. In order to check the validity of the EDMs, we also use these electric dipole moments to calculate the Stark energies by numerical integration. The results agree with those calculated by matrix diagonalization.
基金project supported by the National Natural Science Foundation of China (Grant Nos 60438020 and 60321003), and the Knowledge innovation program of the Chinese Academy of Sciences (Grant No KJCX2-SW-W14).
文摘The coherent exciton plays an important role in the photosynthetic primary process, and its functions are deeply dependent on the orientation arrangements of local transition dipole moments (TDMs). We theoretically and systematically study the physical property of the coherent exciton at different orientation arrangements of the local TDMs in circular light-harvesting (LH) complexes. Especially, if the orientation arrangements are different, the delocalized TDMs of the coherent excitons and the energy locations of the optically active coherent excitons (OACEs) can be obviously different, and then there are more manners to capture, store and transfer light energy in and between LH complexes. Similarly, if the orientation arrangements are altered, light absorption and radiative intensities can be converted fully between the OACEs in the upper and lower coherent exciton bands, and then the blue and red shifts of the absorption and radiative bands of the pigment molecules can occur simultaneously at some orientation arrangements. If the systems are in the vicinities of the critical orientation arrangements, the weak static disorder or small thermal excitation can destroy the coherent electronic excitations, and then the coherent exciton cannot exist any more.
文摘Many of the technology and computational chemistry applications are used to study drugs and their biological effects. Flutab®drug contains Paracetamol, Diphenhydramine and Pseudoephedrine. Ab-initio calculations were performed at DFT/B3LYP and HF methods with three basis sets, namely, STO-3G, 3-21G, and 6-31G(d) in order to calculate the dipole moments of the three constituents of Flutab®drug. The Diphenhydramine compound was found to be the most stable constituent, with the lowest value of dipole moment.
基金supported by the National Natural Science Foundation of China(Grant Nos.12275052,and 12147101)supported by the National Natural Science Foundation of China(Grant Nos.11725520,11675002,and 12235001)+1 种基金Shanghai Natural Science Foundation(Grant No.21ZR1406100)supported by the Institute of High Energy Physics(Contract No.E25153U1)。
文摘The anomalous magnetic(MDM)and electric(EDM)dipole moments of theτlepton serve as crucial indicators of new physics beyond the standard model.Leveraging azimuthal angular asymmetry as a novel tool in ultraperipheral collisions(UPCs),we attain unparalleled precision in the study of these key properties.Driven by the highly linear polarization of coherent photons,this method uniquely enables both the MDM and EDM to contribute to the cos 2φangular distribution in similar magnitudes.Importantly,our approach substantially narrows the parameter space,excluding more than half of it compared to expected UPC-based measurements reliant solely on the total cross-section.This method not only provides improved constraints but also minimizes the need for additional theoretical assumptions,and offers a novel avenue to probe the EDM effects.
基金the National Basic Research Program of China (No.2006CB806003)the National Natural Science Foundation of China (No.10675076)+2 种基金the Natural Science Foundation of Shandong Province (No.Y2006A21)State Key Laboratory of High Field Laser Physics,Shanghai Institute of OpticsFine Mechanics,Chinese Academy of Sciences.
文摘Propagation of a few-cycle laser pulses in a dense V-type three-level atomic medium is investigated based on full-wave Maxwell-Bloch equations by taking the near dipole-dipole (NDD) interaction into account. We find that the ratio, γ of the transition dipole moments has strong influence on the time evolution and split of the pulse: when γ≤ 1, the NDD interaction delays propagation and split of the pulse, and this phenomenon is more obvious when the value of γ is smaller; when γ =√2, the NDD interaction accelerates propagation and split of the pulse.
文摘We systematically study the magnetic dipole moments of multiquark states.In this study,the magnetic dipole moments of possible B^(−)B^(∗−),B^(0)B^(∗−),B^(−)B^(∗0),B^(0)B^(∗0),B_(s)^(0)B^(∗−),B_(−)B_(s)^(∗0),B_(s)^(0)B^(∗0),B^(0)B_(s)^(∗0),and B_(s)^(0)B_(s)^(∗0) states are extracted using light-cone sum rules.We explore the magnetic dipole moments of these states in a molecular picture with spin-parity JP=1^(+).The magnetic dipole moments of hadrons include useful information on the distributions of internal charge and magnetization,which can be used to understand their geometrical shapes and quark-gluon organization.The results of the present study along with the spectroscopic parameters may help future theoretical and experimental research on the characteristics of doubly-bottom tetraquark states.
基金Project supported by the National Natural Science Foundation of China (Grant Nos 20103007 and 20473079).
文摘Stretching vibrational band intensities of XH3 (X=N, Sb) molecules are investigated employing three-dimensional dipole moment surfaces combined with the local mode Hamiltonian model. The dipole moment surfaces of NH3 and SbH3 are calculated with the density functional theory and at the correlated MP2 level, respectively. The calculated band intensities are in good agreement with the available experimental data. The contribution to the band intensities from the different terms in the polynomial expansion of the dipole moments of four group V hydrides (NH3, PH3, AsH3 and SbH3) are discussed. It is concluded that the breakdown of the bond dipole approximation must be considered. The intensity “borrowing” effect due to the wave function mixing among the stretching vibrational states is found to be less significant for the molecules that reach the local mode limit.
基金Project supported by the National Natural Science Foundation of China (Grant No 10174019), the Natural Science Foundation of Henan Province, China (Grant No 2006,140008) and Henan Innovation for University Prominent Research Talents (Grant No 2006KYCX002).Acknowledgement We heartily thank Professor Zhu Zheng-He at Sichuan University for his helpful discussion about the reasonable dissociation limits during the planning stage of these calculations.
文摘The reasonable dissociation limit of the A^1∑+ state ^7LiH molecule is obtained. The accurate dissociation energy and the equilibrium geometry of this state are calculated using a symmetry-adapted-cluster configuration-interaction method in complete active space for the first time, The whole potential energy curve and the dipole moment function for the A^1∑+ state are calculated over a wide internuclear separation range from about 0.1 to 1.4 nm. The calculated equilibrium geometry and dissociation energy of this potential energy curve are of Re=0.2487 nm and De=1.064eV, respectively. The unusual negative values of the anharmonicity constant and the vibration-rotational coupling constant are of ωeXe=-4.7158cm^-1 and αe=0.08649cm^-1, respectively. The vertical excitation energy from the ground to the A^1∑+ state is calculated and the value is of 3.613eV at 0.15875nm (the equilibrium position of the ground state). The highly anomalous shape of this potential energy curve, which is exceptionally flat over a wide radial range around the equilibrium position, is discussed in detail. The harmonic frequency value of 502.47cm^-1 about this state is approximately estimated. Careful comparison of the theoretical determinations with those obtained by previous theories about the A^1∑+ state dissociation energy clearly shows that the present calculations are much closer to the experiments than previous theories, thus represents an improvement.
基金Project supported by the National Natural Science Foundation of China(No.11172111)
文摘Dielectrophoresis (DEP) is one of the most popular techniques for bio-particle manipulation in microfluidic systems. Traditional calculation of dielectrophoretic forces of single particle based on the approximation of equivalent dipole moment (EDM) cannot be directly applied on the dense particle interactions in an electrical field. The Maxwell stress tensor (MST) method is strictly accurate in the theory for dielectrophoretic forces of particle interaction, but the cumbersome and complicated numerical computation greatly limits its practical applications. A novel iterative dipole moment (IDM) method is pre- sented in this work for calculating the dielectrophoretic forces of particle-particle inter- actions. The accuracy, convergence, and simplicity of the IDM are confirmed by a series of examples of two-particle interaction in a DC/AC electrical field. The results indicate that the IDM is able to calculate the DEP particle interaction forces in good agreement with the MST method. The IDM is a purely analytical operation and does not require complicated numerical computation for solving the differential equations of an electrical field while the particle is moving.
基金financially supported by the National Natural Science Foundation of China(No.40672031)
文摘Single-crystal X-ray diffraction structural data of four Fe-Mg tourmalines with different Fe contents from Xinjiang, Sichuan, and Yunnan Provinces, China, were collected at room temperature and-100oC. The intrinsic dipole moments of polyhedra and the total intrinsic dipole moment of the unit cell were calculated. By comparing the intrinsic electric dipole moments of the X, Y, Z, T, and B site polyhedra, it is found that the T site polyhedron makes the greatest contribution to the total intrinsic dipole moment. The pyroelectric coefficients of four Fe-Mg tourmalines were experimentally determined, and the influence of intrinsic dipole moments on their pyroelectric properties was inves-tigated. The experimental results show that, compared with the case at room temperature, the intrinsic dipole moments change with the total Fe content at-100oC in a completely different way. With the decrease of temperature, the total intrinsic dipole moments of tourmaline de-crease. Over the same temperature interval, the pyroelectric coefficients increase with the increase in intrinsic dipole moment.
基金supported by the National Basic Research Program (973) of China (No.10574109)the Zhejiang Provincial Science and Technology Department (No.2007G60G1120019)+1 种基金National Science Foundation of Zhejiang Province (No.Y604064)Zhejiang Gongshang University (No.08-13),China.
文摘The mean-square radius of gyration <S^2>,the mean-square dipole moment <D^2>,the mean-square end-to-end distance <R^2> and their temperature coefficients of unsymmetrical disubstituted poly(methylphenylsiloxane) (PMPS) chains, as a function of stereochemical structure,confomational energies and length of polymers,were studied by using an improved configurational-confomational statistical method based on the rotational-isomeric-state theory.It is found that the increase in isotacticity of P...
文摘Steady-state absorption and fluorescence spectra, and time-resolved fluorescence spectra of coumarin 343 (C343) were measured in different solvents. The effect of the solvent on the spectral properties and dipole moment of the lowest excited state of C343 were investigated. It was found that the absorption and fluorescence spectra red-shifted slightly and strongly with increasing solvent polarity, respectively, because the charge distribution of the excited state leaded to the increasing difference between the absorption and fluorescence spectra with increasing solvent polarity. The dipole moment of the lowest excited state of C343 was determined from solvatochromic measurements and the quantum chemical calculation, and the results obtained from these two methods were fully consistent. Investigations of the time-resolved fluorescence of C343 in different solvents indicated that the fluorescence lifetimes increased nearly linearly with 4.45 ns in water. This can be ascribed between C343 and hydrogen donating increasing solvent polarity from 3.09 ns in toluene to to the intermolecular hydrogen bonding interactions solvents
基金supported by the National Natural Science Foundation of China(Grant Nos.11374217 and 11474207)
文摘An accurate electric dipole moment function(EDMF) is obtained for the carbon monoxide(CO) molecule(X1+Σ)by fitting the experimental rovibrational transitional moments. Additionally, an accurate ab initio EDMF is found using the highly accurate, multi-reference averaged coupled-pair functional(ACPF) approach with the basis set, aug-cc-p V6 Z, and a finite-field with ±0.005 a.u.(The unit a.u. is the abbreviation of atomic unit). This ab initio EDMF is very consistent with the fitted ones. The vibrational transition matrix moments and the Herman–Wallis factors, calculated with the Rydberg–Klein–Rees(RKR) potential and the fitted and ab initio EDMFs, are compared with experimental measurements. The consistency of these line intensities with the high-resolution transmission(HITRAN) molecular database demonstrates the improved accuracy of the fitted and ab initio EDMFs derived in this work.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB01010200)the Hundred Talents Program of the Chinese Academy of Sciences(Grant No.Y321311401)+2 种基金the National Natural Science Foundation of China(Grant Nos.61475139,11347147,and11247014)the National Basics Research Program of China(Grant No.2013CB329501)the Zhejiang Provincial Natural Science Foundation(Grant No.LQ13A040006)
文摘A dressed-state perturbation theory beyond the rotating wave approximation (RWA) is presented to investigate the interaction between a two-level electronic transition of polar molecules and a quantized cavity field. Analytical expressions can be explicitly derived for both the ground- and excited-state-energy spectrums and wave functions of the system, where the contribution of permanent dipole moments (PDM) and the counter-rotating wave term (CRT) can be shown separately. The validity of these explicit results is discussed by comparison with the direct numerical simulation. Compared to the CRT coupling, PDM results in the coupling of more dressed states and the energy shift is proportional to the square of the normalized permanent dipole difference, and a greater Bloch-Siegert shift can be produced in the giant dipole molecule cavity QED. In addition, our method can also be extended to the solution of the two-level atom Rabi model Hamiltonian beyond the RWA.
基金supported by the National Natural Science Foundation of China(No.21533003,No.21773081 and No.22073035)。
文摘Recently,more attention have been paid on the construction of dipole moment functions(DMF)using theoretical methods.However,the computational methods to construct DMFs are not validated as much as those for potential energy surfaces do.In this letter,using Ar…He as an example,we tested how spectroscopyaccuracy DMFs can be constructed using ab initio methods.We especially focused on the basis set dependency in this scenario,i.e.,the convergence of DMF with the sizes of basis sets,basis set superposition error,and mid-bond functions.We also tested the explicitly correlated method,which converges with smaller basis sets than the conventional methods do.This work can serve as a pictorial sample of all these computational technologies behaving in the context of constructing DMFs.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.91421305,91121005,and 11674359)the National Key Basic Research Program of China(Grant No.2013CB922003)
文摘We report a sensitive detection of high Rydberg atom with large dipole moment utilizing its deflection near a pair of parallel cylindrical copper rods which are oppositely charged. When the low-field seeking state Rydberg atoms fly across the gradient electric field formed by the pair of rods, they will be pushed away from the rods while the high-field seeking state ones will be attracted towards the rods. These atoms will form different patterns on an ion imaging system placed downwards at the end of the rods. The spatial distribution of the deflected atoms on the imaging system is also simulated, in good agreement with the experimental results, from which we can deduce the quantum state information of the excited atoms. This state resolvable Rydberg atom detection can be used for the dynamics research of the dipole-dipole interaction between atoms with large dipole moments.
基金Supported by the National Key Research and Development Program of China under Grant No 2017YFA0304203the National Natural Science Foundation of China under Grant Nos 61675120 and 11434007+3 种基金the National Natural Science Foundation of China for Excellent Research Team under Grant No 61121064the Shanxi Scholarship Council of China,the 1331KSCthe PCSIRT under Grant No IRT13076the Applied Basic Research Project of Shanxi Province under Grant No 201601D202008
文摘The transition dipole moments(TDMs) of ultracold85 Rb133 Cs molecules between the lowest vibrational ground level, (X^1Σ~+( v= 0, J= 1), and the two excited rovibrational levels, 2~3Π0+(v′= 10, J′= 2) and 2~1Π1(v′= 22,J′= 2), are measured using depletion spectroscopy. The ground-state85 Rb133 Cs molecules are formed from cold mixed component atoms via the 2~3Π0-( v= 11, J= 0) short-range level, then detected by time-of-flight mass spectrum. A home-made external-cavity diode laser is used as the depletion laser to couple the ground level and the two excited levels. Based on the depletion spectroscopy, the corresponding TDMs are then derived to be 3.5(2)×10^(-3)eαα and 1.6(1)×10^(-2)eαα, respectively, where 0)(60 represents the atomic unit of electric dipole moment. The enhance of TDM with nearly a factor of 5 for the 21Π1(v′= 22, J′= 2) excited level means that it has stronger coupling with the ground level. It is meaningful to find more levels with much more strong coupling strength by the represented depletion spectroscopy to realize direct stimulated Raman adiabatic passage transfer from scattering atomic states to deeply molecular states.