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991.
Ulrich Meier Christoph Van Wüllen Michael Schindler 《Journal of computational chemistry》1992,13(5):551-559
A direct method for the ab initio calculation of the magnetic susceptibility and chemical shielding tensors based on the individual gauge for localized molecular orbitals (IGLO) formalism is introduced. “Direct” in this context means we avoid storing the two-electron repulsion integrals in favor of recalculating them whenever necessary. In conjunction with the Direct-SCF package TURBOMOLE Direct IGLO (DIGLO) permits calculation of magnetic second-order properties for large molecules by minimizing peripheral disc storage requirements. The size of the molecules to be treated is limited only by the amount of CPU time available. The performance of DIGLO is demonstrated for some selected examples. 相似文献
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There is presented a modified method of contracting compacta that gives an estimate of the error of approximate solutions of certain ill-posed problems in the case when all initial data are measured with a preassigned exactness.Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 43, No. 12, pp. 1693–1696, December, 1991. 相似文献
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A.L. Vasiliev E.A. Stepantsov Z.G. Ivanov E. Olsson K. Verbist G. Van Tendeloo 《Interface Science》1997,5(4):223-230
The structure of the artificial grain boundaries in Al2O3 bicrystals withY3Al5O12 and Y-stabilizedZrO2 (Y-ZrO2) intermediate layers was studiedwith high resolution electron microscopy, electron diffraction and energydispersive X-ray analysis. TheY3Al5O12 intermediate layer wasfound to be polycrystalline with three different orientation relationshipsbetween the 2O3 and theY3Al5O12. The structure of theY3Al5O12/2O3 interfaces is described.Also2O3 bicrystals with an Y-ZrO2/2O3/Y-ZrO2/2O3/Y-ZrO2intermediate layer, prepared at two different temperatures, werestudied.Recry stallization of the intermediate layers occurred during thesolid phase intergrowth of the 2O3 bicrystalsparts and only an Y-ZrO2 layer was found as intermediatelayer. The misorientation between the consecutive Y-ZrO2grains was less than 1.5°. Misfit dislocations and atomic height stepsdecorate the Y-ZrO2/2O3interface. 相似文献
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999.
J.-F. Colomer L. Henrard Ph. Lambin G. Van Tendeloo 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,27(1):111-118
The atomic structure of single-wall carbon nanotube bundles produced by three different techniques (laser ablation, electric
arc discharge and catalytic chemical vapor deposition (CCVD)) has been characterized by electron diffraction and microscopy.
Information on the helicity and the lattice packing has been obtained. Concerning the helicity, small bundles produced by
CCVD exhibit only one or two tube helicities within a single bundle. The diffraction patterns of laser-ablation produced bundles
also present well-defined but more diversified chiralities within a single bundle. By contrast the data acquired on bundles
formed by arc discharge show a more diffuse pattern, characteristic of a random chirality dispersion within a single bundle.
Concerning the lattice packing, informations are obtained via a detailed study of the equatorial line of the diffraction pattern for bundles produced by the three techniques. This electron
diffraction study is completed by high-resolution electron microscopy.
Received 8 August 2001 and Received in final form 14 March 2002 相似文献
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