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41.
JOSE PITARCH-RUIZ JOSE SANCHEZ-MARIN ALFREDO SANCHEZ DE MERAS DANIEL MAYNAU 《Molecular physics》2013,111(3):483-494
The vertical electronic spectrum of formaldehyde has been studied by means of (SC)2-MR-SDCI and CCLR methods. Two basis sets of atomic natural orbitals (ANOs) complemented with a one-centre series of Rydberg orbitals were used. The first was taken from the CASPT2 study by Merchán, M., and Roos, B. O., 1995, Theoret. Chim. Acta, 92, 221, and may be described as C,O[4s3pld]/H[2slp] with a lslpld Rydberg series centred in the charge centroid of the 2B2 state of the cation. The second was a larger basis set that may be described as C,O[6s5p3d2f]/H[4s3p2d] + 3s3p3d in the same centre. The (SC)2 dressing may be applied efficiently to an MR-SDCI method and comparison with the dressed CAS-SDCI is satisfactory, in spite of the remarkable reduction in the CI space dimension. The consistency of the (SC)2-MR-SDCI results was tested also against the CCLR and CASPT2 results using the same basis sets and against the CCLR results using Dunning's aug- and daug-cc-pVQZ basis sets. The 3A1(π → π *) state is correctly placed as the second excited triplet while the highly multi-configurational nature of the 1A1(π → π *) state is confirmed as well as its greatly mixed valence-Rydberg nature. This state is predicted as lying under the 10 eV level, on top of the (ny → 3d) Rydberg states that are predicted in the 8.9–9.5eV region. The 5 1B2(ny → 4s) Rydberg state and the 1B2(σy → π*) also are predicted in this region. The triplet states also were calculated with the (SC)2-MR-SDCI method. The vertical ordering of the 2 1A1(ny → 3py) and 2 1B2(ny → 3pz) states is discussed, as well as that of the 1B1(σ → π*) and the Rydberg 1B1(ny → 3dxy) states. This work shows the highly reliable values that may be reached applying the dressing method along with a large basis set. Such a procedure is made possible using an MR-SDCI selection of spaces instead of the CAS-SDCI that was used up to now in most (SC)2 dressing applications. 相似文献
42.
The composition-independent virial coefficients of a d-dimensional binary mixture of (additive) hard hyperspheres following from a recent proposal for the equation of state of the mixture (Santos, A., Yuste, S. B., and López de Haro, M., 1999, Molec. Phys., 96, 1) are examined. Good agreement between theoretical estimates and available exact or numerical results is found for d = 2, 3, 4 and 5, except for mixtures whose components are very disparate in size. A slight modification that remedies this deficiency is introduced and the resummation of the associated virial series is carried out, leading to a new proposal for the equation of state. The case of binary hard sphere mixtures (d = 3) is analysed in some detail. 相似文献
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44.
Multiconfigurational perturbation theory (CASPT2) and difference dedicated configuration interaction (DDCI) are applied to study the ferrimagnetic coupling in an oxamido-bridged Mn(II)Cu(II) molecular species. CASPT2 reproduces the experimental coupling very well. From the partition of the CASPT2 energy, the most important contributions to the coupling are established. Spin populations are calculated with DDCI. The successive improvement of the N-electron wave function allows us to analyse the contributions to the spin delocalization. 相似文献
45.
BARB FLORIN DAN; DE KONING WILLEM L.; IONESCU VLAD 《IMA Journal of Mathematical Control and Information》1995,12(3):253-298
This paper represents a Popov-theory-based assessment of thecurrent status of the digital control of infinitedimensionalsystems with certain unboundedness in control and/or observation,summarizing some results and indicating which, in the authors'opinion, would be the promising directions for future research. 相似文献
46.
This paper deals with robustness of adaptive control of continuoussystems subject to known output delay, input saturation, unmodelledlinear dynamics, and bounded disturbances. A simple gradient-typealgorithm with a relative deadzone is used. The relative deadzoneis built with an estimated contribution of the unmodelled dynamicsto the system output. The basic tool used for stability androbustness analysis is Gronwall's lemma. 相似文献
47.
The authors present the results of some simulation studies concerned with the computer control of signalized intersections. The simplest model considered is that of two competing random streams. The transient response and delay/flow characteristics of some simple control procedures are investigated. These are based on the Dunne-Potts policy in which the traffic light is switched when the queue of the road with right of way has been dispersed.The model is then developed to consider four competing streams and the control policies are modified accordingly. Similar results to the two-stream case are presented. In the final section turning vehicles are considered by including eight competing streams in the intersection model. 相似文献
48.
49.
J. Simpson M.A. Riley R.W. Laird D.J. Hartley F.G. Kondev J. Sweeney A.N. Wilson S.J. Gale M.A. Bentley A.M. Bruce R. Chapman R.M. Clark D.M. Cullen P. Fallon P.D. Forsyth S.J. Freeman P.M. Jones J.C. Lisle A.O. Macchiavelli J.F. Sharpey-Schafer A.G. Smith J.F. Smith D.M. Thompson 《The European Physical Journal A - Hadrons and Nuclei》1998,1(3):267-274
A series of new strongly coupled high-K, multi-quasiparticle structures have been observed in the light erbium transitional
nuclei, 159Er and 160Er. The interpretation of these bands is discussed within the framework of the cranked shell model. These sequences, when
taken together with the existing quasiparticle excitations, form a near complete set of low-lying, multi-quasiparticle structures
on which a coherent series of aligned angular momentum, band crossing and blocking arguments can be based. The measured B(M1)/B(E2)
ratios are compared with geometrical calculations to test the proposed configuration assignments.
Received: 19 November 1997 相似文献
50.