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351.
We demonstrate experimentally that, in a tight focusing geometry, circularly polarized femtosecond laser vortex pulses ablate material differently depending on the handedness of light. This effect offers an additional degree of freedom to control the shape and size of laser-machined structures on a subwavelength scale.  相似文献   
352.
A crystal of the title complex [Pt(DMSO)(GT)] ( 1a ), where H2GT = glyoxylic acid thiosemicarbazone, has been characterized by X‐ray crystallography and its structure has been compared with that of the recently described cytotoxic complex [Pt(DMSO)(GT)]·DMSO (1). The crystal of 1a is monoclinic; space group P 21/n; unit cell dimensions: a = 7.3270(10), b = 10.313(2), c = 13.706(3) Å, β = 101.92(3)°; V = 1013.3(3) Å3; Z = 4. The Pt(II) ion is approximately planar tetragonal coordinated by the carboxylato oxygen, azomethine nitrogen and thiolato sulfur atom of the doubly deprotonated H2GT molecule, and the sulfur atom of DMSO. The two five membered chelate rings are almost coplanar. In distinct with 1 , the sulfoxide oxygen atom and thiolato sulfur atom are in gauche position. A system of hydrogen bonds of the type N–H···O involving the amino, carboxylato and sulfoxide groups links the complex molecules within the unit cells. The ππ stacking pattern between the chelate rings in 1a involves centrosymmetric pairs of complex molecules and differs from that in 1 . (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
353.
The paper is concerned with the problem of system modelling in the case of many decision makers with conflicting goals. The suggested approach, preserving much of the tractability of the standard LQG problems, allows to take into account decision makers' risk attitudes. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
354.
Isomorphous triclinic forms of di­chloro­[phthalocyaninato(2−)]­tin(IV), [Sn(C32H16N8)Cl2], and di­chloro­[phthalocyaninato(2−)]­ger­manium(IV), [Sn(C32H16N8)Cl2], and a monoclinic form of the latter have been obtained from the reaction of pure tin and germanium powder, respectively, with phthalo­nitrile under a stream of ICl vapour. All three crystal structures consist of centrosymmetric [SnPcCl2] and [GePcCl2] [Pc is phthalocyaninate(2−)] mol­ecules, which are separated but interacting. In the triclinic forms (Sn and Ge), the Pc macrocycles are not staggered but slipped, and in the monoclinic form (Ge), the mol­ecules are additionally inclined. In both cases, the central Sn or Ge atom is six‐coordinated by the four iso­indole N atoms of the Pc macrocyclic ligand and by two Cl atoms (located trans) into a tetragonal–bipyramidal structure. The arrangement of [SnPcCl2] and [GePcCl2] mol­ecules in the crystal structure is determined mainly by intermolecular C—H⃛Cl, π–π and van der Waals interactions.  相似文献   
355.
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