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71.
Structural evolution of odd-even and odd-odd Mn isotopes from the valley of stability up to neutron dripline is studied in the framework of the self-consistent mean-field theory of Hartree–Fock–Bogoliubov. Three Skyrme effective interactions, namely, SLy4, SLy5 and SLy5T, are employed to investigate the tensor force effect on the ground-state properties. It is shown that the calculated quantities with the SLy4 interaction correctly reproduce the available experimental data and agree well with finite range droplet model and relativistic mean-field predictions. An inconsistency has been observed between the curves of the separation energies and that of the charge radius around N = 40. It is explained by the flatness of the potential energy curves in this region. The SLy5 and SLy5T results point to the necessity to refit all the Skyrme parameters after including the tensor terms. 相似文献
72.
过去几十年中,原子核物理的相对论密度泛函理论得到很大发展,可以成功地描述各种原子核现象。文章阐述在相对论框架下研究原子核多体问题的必要性,介绍原子核物理中相对论密度泛函理论的基本概念,回顾相对论密度泛函理论在描述原子核基态、手征转动和动力学过程等方面的应用,讨论基于原子核物理的相对论第一性原理研究,即完全自洽的相对论Brueckner—Hartree—Fock理论,构建微观普适的密度泛函的基本思想。 相似文献
73.
A previous theory for studying the distribution of non-uniform fields in multiple-quantum-well photodetectors under an ac voltage is generalized by including non-adiabatic space-charge-field effects. Numerical calculations indicate that field-domain effects are only important at high temperatures or high voltages when both injection and sequential-tunneling currents are significant. On the other hand, it is found that the non-adiabatic effects included in this generalized theory become significant at low temperatures and low voltages when field-domain effects are negligible. In order to explain the non-adiabatic charge-density fluctuations quantum-statistically, a non-adiabatic differential equation is derived based on the self-consistent Hartree model by using a shifted Fermi–Dirac model for the local fluctuation of electron distributions. The non-adiabatic effect is found to cause an “equilibrium” state variation with time under an ac voltage. 相似文献
74.
The molecular improved generator coordinate Hartree–Fock (MIGCHF) method is used to generate increasing size atom-centered Gaussian basis sets for the CO2 molecule. From these basis sets total HF energies and second-order correlation energies were calculated and compared with results obtained with other approaches. Considering our largest basis set, the HF energy is in error by 98 hartree and the second-order correlation energy corresponds to 95.6% of an estimate of the limiting value. The relevance of the present calculations is to show the accuracy that can be achieved in studies of small polyatomic molecules with the MIGCHF method.Acknowledgement We acknowledge the financial support of CNPq (Brazilian Agency). We employed computational facilities at Universidade Federal do Espírito Santo and Universidade Estadual Paulista (IQ Araraquara). 相似文献
75.
Kodai Kanemaru Yoshihiro Watanabe Norio Yoshida Haruyuki Nakano 《Journal of computational chemistry》2023,44(1):5-14
A combined method of the Dirac–Hartree–Fock (DHF) method and the reference interaction-site model (RISM) theory is reported; this is the initial implementation of the coupling of the four-component relativistic electronic structure theory and an integral equation theory of molecular liquids. In the method, the DHF and RISM equations are solved self-consistently, and therefore the electronic structure of the solute, including relativistic effects, and the solvation structure are determined simultaneously. The formulation is constructed based on the variational principle with respect to the Helmholtz energy, and analytic free energy gradients are also derived using the variational property. The method is applied to the iodine ion (I−), methyl iodide (CH3I), and hydrogen chalcogenide (H2X, where X = O–Po) in aqueous solutions, and the electronic structures of the solutes, as well as the solvation free energies and their component analysis, solvent distributions, and solute–solvent interactions, are discussed. 相似文献
76.
Weinhold's natural hybrid orbitals can be chosen as the molecular adapted atomic orbitals to build the canonical molecular orbitals of N2 molecules. The molecular Fock matrix expanded in the natural hybrid orbitals can reveal deeper insight of the electronic structure and reaction of the N2 molecule. For example, the magnitude of Fab can signify the bonding character of the paired electrons as well as the diradical character of the unpaired electrons for both σ‐ and π‐types. Discarding the concept of the overlap between non‐orthogonal atomic orbitals, the different orbitals for different spins in the unrestricted Hartree‐Fock wavefunction reveal that there are three pairs of opposite spin density flows between two atoms, which proceed until the bonding molecular orbitals form. 相似文献
77.
In this article, as a first step to develop an efficient approximation for predicting the molecular electronic excited state properties at ab initio level, we propose local excitation approximation (LEA). In the LEA scheme, the only local electron excitations within selected substructure (Chromophore) are treated to calculate the targeted excited state wavefunctions, whereas the other electron excitations (local electron excitations in other substructure and charge‐transfer excitations between different regions) are simply discarded. This concept is realized by using the localized molecular orbitals (LMO) localizing on the chromophore substructure. If the targeted transitions show the strong local character and the adequate substructure is selected as chromophore region, the LEA scheme can provide excited state properties without large loss of accuracy. The fatal slowdown of convergence speed of Davidson's iterative diagonalization due to the use of LMO can be avoided by additional transformation of LMOs. To assess the accuracy and efficiency of the LEA scheme, we performed test calculations using various compounds at configuration interaction single (CIS) and time‐dependent Hartree‐Fock (TDHF) level of theory. © 2009 Wiley Periodicals, Inc. J Comput Chem, 2009 相似文献
78.
The spectroscopic parameters of the ground state of thallium hydride are obtained using the four-component relativistic Dirac–Coulomb–Gaunt–coupled-cluster
wave function with single and double excitations and an estimated triples correction method. Core correlation effects make
the bond weaker but have little effect on the bond length. Inclusion of the distance dependence of the Gaunt part of the two-electron
Breit interaction has an opposite but smaller effect on these properties.
Received: 8 September 2000 / Revised version: 5 October 2000 / Published online: 21 December 2000 相似文献
79.
Knut Faegri Jr 《Theoretical chemistry accounts》2001,105(3):252-258
A series of energy-minimized relativistic Gaussian basis sets for the elements with atomic numbers 19–118 is presented. The
basis sets have been derived at the self-consistent field level as weighted average energies of the respective electronic
configurations. A spherical Gaussian charge distribution has been used to model the nucleus. The basis sets are constructed
as interleaving dual family sets with shared exponents within each family. The quality of the basis sets is better than double
zeta.
Received: 7 July 2000 / Accepted: 21 September 2000 / Published online: 21 December 2000 相似文献
80.
The paper concerns the Cauchy and scattering problem of the wave equation of Hartree type with small initial data with fast decay. We prove weighted estimates for a convolution which appears in the equation. 相似文献