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81.
缀饰态理论在碰撞能量转移过程中的应用   总被引:1,自引:0,他引:1  
王立  张小安  杨振辉  董庆彦 《光子学报》2002,31(9):1069-1072
利用缀饰态理论研究了由分子和原子组成的混合共振系统中分子和原子之间的碰撞能量转移过程.结果发现:在单模强激光场作用下,该混合共振系统由于发生了碰撞能量转移,而使得粒子在相应能级上产生重新布居,并在一定条件下呈现出量子干涉增强效应,导致了不同缀饰态能级之间出现交叠区.这一结果与现有实验报导相符,为研究多能级系统的量子干涉效应提供了一种新的理论途径.  相似文献   
82.
We study the relationship between the Dirichlet problem and the Cauchy problem with inhomogeneous boundary conditions for local operators. Our results are applied to non-autonomous parabolic problems on non-cylindrical domains. Received January 10, 2001; accepted April 5, 2001.  相似文献   
83.
An approximate method for the vibration-vibration (V-V) energy transfer process during collinear collisions of two HF molecules involving low-lying states in the presence of infrared laser beam using a quasi-energy approach (non-perturbative) is presented. The effect of radiation on V-V process is investigated by changing the laser field detuning and power for various values of collision velocities.  相似文献   
84.
凌寅生  凌天 《光学学报》1995,15(1):26-128
应用传播子方法,求解福克-普朗克方程。应用局域谐振子势近似,计算格林函数。计算范德波尔振子方程的瞬态解。  相似文献   
85.
This article revisits Feynman‘s characteristic function, and points out the insight and usefulness of hisphysical interpretation. As an example, the tedious and rather long derivation of the propagator in polar coordinatescan be easily and clearly obtained by merely using Feynman‘s physical intepretation of the characteristic function andsome well-known results of central force problem.  相似文献   
86.
87.
An alternative way to calculate vertical ionization potentials (VIP) and vertical electron affinity (VEA) is the application of Koopman's theorem, using the electron propagator theory. In the present work, the results of the application of this theorem using the electron propagator formalism have been compared with the experiment in order to validate different basis set. Using the basis set with the best performance, the acidity tendencies in some substituted acetic acid molecules have been analyzed by correlating the proton affinity (PA) with molecular electronegativity (χ) and hardness (η); these last indexes were obtained from the calculated VIP and VEA considering the finite difference approximation. The above correlations were compared with equivalent correlations using the energy of the frontier Hartree–Fock orbitals and the corresponding Kohn–Sham orbitals, which were calculated with the B3LYP‐DFT procedure. The results indicate that the electron propagator theory could be an interesting alternative to evaluate reactivity indexes, since this theory gives reliable values of VIP and VEA. It was also found that (i) the VIP values are very close to experiment, with only a 0.38% of error; (ii) acceptable results are inferred for VEA; (iii) a triple zeta quality function works quite well in these calculations, and particularly the 6‐311G(d,p) basis set is the best, as it had been reported; and (iv) using the depronation energy (DPE), good results were obtained in the correlations δDPE‐VEA and δDPE‐χ. The results tested that P3 approximation in the electron propagator approach can be a new and interesting alternative in predicting VIP, VEA, and some reactivity indexes, such as χ and η, at least for the compounds studied. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2006  相似文献   
88.
We present a Fourier grid Hamiltonian‐based multidimensional propagator method for multiphoton dissociation dynamics of triatomic molecule in continuous, pulsed, and bichromatic laser field. The method has been successfully applied to the photodissociation dynamics of HCN molecule, i.e., collinear geometry. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2007  相似文献   
89.
The multiconfigurational spin tensor electron propagator (MCSTEP) method was developed as an implementation of electron propagator/single particle Green's function methods. MCSTEP was specifically designed for open‐shell and highly correlated (nondynamically correlated) initial states. Ionization or electron attachment is always from a state of pure spin symmetry to a state of pure spin symmetry even if the initial state is open shell. MCSTEP can be used as well for molecules with initial states that can be accurately described by a single determinant‐based theory. The initial state that is used in MCSTEP is typically a small complete active space (CAS) multiconfigurational self‐consistent field (MCSCF) state. We previously examined different small CAS choices for MCSTEP initial states and have developed a generally workable scheme. This article further examines some different ways to choose the CAS for MCSTEP. With several logical CAS choices, we have calculated the low‐lying vertical MCSTEP ionization potentials (IPs) of C2, N2, linear H2O, O2, CH2, and NH2, comparing them with large multireference configuration interaction (MRCI) calculations. We conclude that generally a small modification and extension of our previous schemes for choosing the MCSTEP CAS gives IPs that most effectively mimics the results of large scale MRCI IPs in general. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2007  相似文献   
90.
The multiconfigurational spin tensor electron propagator method (MCSTEP) was developed as an implementation of electron propagator/single particle Green's function methods for ionization potentials (IPs) and electron affinities (EAs). MCSTEP was specifically designed for open shell and highly correlated (nondynamically correlated) initial states. For computational efficiency the initial state used in MCSTEP is typically a small complete active space (CAS) multiconfigurational self‐consistent field (MCSCF) state. If in a molecule there are some degenerate orbitals which are not fully or half occupied, usual MCSCF calculations will make these orbitals inequivalent, i.e., the occupied ones will be different from the nonoccupied ones, so that the degeneracy is broken. In this article, we use a state averaged MCSCF method to get equivalent orbitals for the initial state and import the integrals into the subsequent MCSTEP calculations. This gives, in general, more reliable MCSTEP vertical IPs. © 2008 Wiley Periodicals, Inc., 2008  相似文献   
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