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101.
采用相对论和非相对论理论模型可描述奇异核的性质 .相对论平均场理论预言了2 6,2 7,2 8P存在一个质子晕 ,而27,28,29S存在两个质子晕 .最近 ,MSU的最新的实验发现了2 6,2 7,2 8P核存在一个质子晕.采用相对论 Hartree- Fock理论研究了 Fock项和矢量介子对奇异核性质的贡献,研究表明交换项和矢量介子对非常丰中子核性质的影响非常不同于对稳定线附近核性质的影响.同时,采用形变的Hartree- Fock- Bogoliubov理论研究了某些轻核同位素链的性质和形变. 相似文献
102.
B. J. van der Veken R. S. Sanders J. Xiao J. R. Durig 《Journal of Molecular Structure》2001,560(1-3):57-86
Infrared spectra (4000–50 cm−1) of the vapor, amorphous and crystalline solids and Raman spectra (3600–10 cm−1) of the liquid with qualitative depolarization data as well as the amorphous and crystalline solids of methylaminothiophosphoryl difluoride, CH3N(H)P(=S)F2, and three deuterated species, CD3N(H)P(=S)F2, CH3N(D)P(=S)F2, and CD3N(D)P(=S)F2, have been recorded. The spectra indicate that in the vapor, liquid and amorphous solid a small amount of a second conformer is present, whereas only one conformer remains in the low temperature crystalline phase. The near-infrared spectra of the vapor confirms the existence of two conformers in the gas phase. Asymmetric top contour simulation of the vapor shows that the trans conformer is the predominant vapor phase conformer. From a temperature study of the Raman spectrum of the liquid the enthalpy difference between the trans and near-cis conformers was determined to be 368±15 cm−1 (4.41±0.2 kJ/mol), with the trans conformer being thermodynamically preferred. Ab Initio calculations with structure optimization using the 6-31G(d) and 6-311+G(d,p) basis sets at the restricted Hartree–Fock (RHF) and/or with full electron correlation by the perturbation method to second order (MP2) support the occurrence of near-trans (5° from trans) and near-cis (20° from cis) conformers. From the RHF/6-31G(d) calculation the near-trans conformer is predicted to be the more stable form by 451 cm−1 (5.35 kJ/mol) and from the MP2/6-311+G(d,p) calculation by 387 cm−1 (4.63 kJ/mol). All of the normal modes of the near-trans rotamer have been assigned based on infrared band contours, depolarization values and group frequencies and the assignment is supported by the normal coordinate calculation utilizing harmonic force constants from the MP2/6-31G(d) ab initio calculations. 相似文献
103.
Asao Arai 《Acta Appl Math》2000,63(1-3):41-78
We consider arithmetical aspects of analysis on Fock spaces (Boson Fock space, Fermion Fock space, and Boson–Fermion Fock space) with applications to analytic number theory. 相似文献
104.
105.
Considering the intrinsic decoherence proposed by Milburn, we
investigate the entanglement between two two-level atoms induced
by a Fock state of single-mode quantized radiation field. The
time-dependent reduced density matrix of the atoms system is given
explicitly. Due to the intrinsic decoherence, the atoms system
will approach a stationary state, where the stationary entanglement
depends on the initial states of the field and the atoms. 相似文献
106.
Ida-Marie Høyvik 《Molecular physics》2020,118(4)
In the previously introduced multilevel Hartree–Fock (HF) model, the electronic density is optimised in a given region of the molecular system. The approach is based on generating an active occupied and active virtual space by decomposing a start guess density for the entire system. In this work, a diagonalisation based implementation for Roothaan–Hall (RH) with direct inversion in iterative subspace (DIIS) and a quasi-Newton minimisation procedure using the augmented RH (ARH) approach are described for accelerating convergence for the multilevel HF model. The equations are derived to be consistent with convergence acceleration for traditional atomic orbital based HF calculations. The main idea is to formulate all quantities in the molecular orbital basis to exploit that the active molecular orbital basis is significantly smaller than the atomic orbital basis, and thus enable the application of wave function approaches that are well-studied for small molecular systems to large molecular systems. Thus, all equations are formulated such that no atomic orbital density or Fock matrices are needed for the DIIS and ARH algorithms. Results show that the acceleration schemes yield efficient optimisation of the multilevel HF wave function. 相似文献
107.
《Physics letters. A》2020,384(17):126354
In a recent research (Olivares et al., 2019 [18]) we have demonstrated that a homodyne-like scheme, exploiting a “low-intensity” local oscillator, can be used to perform optical state tomography of both quantum and classical states of light. The reconstruction method directly uses the homodyne-like probability distribution retrieved from the detector. Here, we further investigate the role played by the local oscillator in this respect. In particular, we study to some extent how its intensity affects the quantum-state reconstruction procedure by focusing on the case of the Fock states |1〉 and |2〉, whose homodyne-like probability distributions are sensibly affected by the actual value of the LO intensity. The analysis is performed on Monte Carlo simulated experiments taking also into account the quantum detection efficiency. 相似文献
108.
Un Cig Ji 《Journal of Functional Analysis》2003,201(1):1-29
The quantum stochastic integral of Itô type formulated by Hudson and Parthasarathy is extended to a wider class of adapted quantum stochastic processes on Boson Fock space. An Itô formula is established and a quantum stochastic integral representation theorem is proved for a class of unbounded semimartingales which includes polynomials and (Wick) exponentials of the basic martingales in quantum stochastic calculus. 相似文献
109.
The time-dependent Hartree–Fock approach is employed with the aug-cc-pVDZ or 6-311++G** basis set to simulate, in the harmonic approximation, the hyper-Raman spectra of ethylene, ethane, and dimethyl ether. Comparison with the experiment of Verdieck etal. [(1970) Chem. Phys. Lett. 7:219] is performed for ethylene and ethane. Effects of the polarization of the incident light and the detected light are studied for ethylene. Special focus is given on these vibrational normal modes that cannot be detected in IR and Raman spectroscopies.Contribution to the Jacopo Tomasi Honorary Issue 相似文献
110.
We formulate a theory of generalized Fock spaces which underlies the different forms of quantum statistics such as ‘infinite’,
Bose-Einstein and Fermi-Dirac statistics. Single-indexed systems as well as multi-indexed systems that cannot be mapped into
single-indexed systems are studied. Our theory is based on a three-tiered structure consisting of Fock space, statistics and
algebra. This general formalism not only unifies the various forms of statistics and algebras, but also allows us to construct
many new forms of quantum statistics as well as many algebras of creation and destruction operators. Some of these are: new
algebras for infinite statistics,q-statistics and its many avatars, a consistent algebra for fractional statistics, null statistics or statistics of frozen
order, ‘doubly-infinite’ statistics, many representations of orthostatistics, Hubbard statistics and its variations. 相似文献