排序方式: 共有5条查询结果,搜索用时 31 毫秒
1
1.
《Journal of Coordination Chemistry》2012,65(9):1385-1398
The reaction of trans(N)-[Co(D-pen)2]? (pen = penicillaminate) or trans(N)-[Co(L-pen)2]? with [MCl2(L)] (M = Pd or Pt, L = 2,2′-bipyridine (bpy) or 4,4′-dimethyl-2,2′-bipyridine (dmbpy)) stereoselectively gave an optically active S-bridged dinuclear complex, [M(L){Co(D-pen)2}]Cl · 3H2O or [M(L){Co(L-pen)2}]Cl · 3H2O. The mixture of equimolar amounts of these two enantiomers in H2O crystallizes as [M(L){Co(D-pen)2}]0.5[M(L){Co(L- pen)2}]0.5Cl · nH2O (1cCl · 7H2O: M = Pd, L = bpy, n = 7; 2cCl · 7H2O: M = Pd, L = dmbpy, n = 7; 3cCl · 6H2O: M = Pt, L = dmbpy, n = 6), in which the enantiomeric complex cations are included in the ratio of 1 : 1. In the crystals of 1cCl · 7H2O, [Pd(bpy){Co(D-pen)2}]+ (1a) and [Pd(bpy){Co(L-pen)2}]+ (1b) are arranged alternately while overlapping the bpy planes along the a axis, and the π electronic systems of bpy moieties interact with each other. This is quite a contrast to the optically active 1aCl · 3H2O or 1bCl · 3H2O, which exist as monomers without intermolecular interactions. In crystals of 2cCl · 7H2O and 3cCl · 6H2O, similarly, the two enantiomeric complex cations interact with each other through the dmbpy frameworks. However, the interplane distances between the stacked π systems in these dmbpy complexes are considerably longer than in the bpy complexes. Such structural characteristics significantly reflect their diffuse reflectance spectra. 相似文献
2.
We have added time resolution to laser-induced breakdown spectroscopy in two forms, by gating an optical multichannel analyzer (OMA) and by time-resolving the output of a photomultiplier with a boxcar amplifier. Spectra were obtained for temporal segments of 25 to 100 ns, from 25 ns to 50 µs after initiation of the breakdown. OMA spectra of oxygen illustrate the power of this technique for survey purposes. The photomultiplier-boxcar arrangement was used to detect phosphorus atoms from diisopropylmethyl phosphonate in air, and also to detect chlorine in air, both in real time. In the former experiments we detected 690 ppm (w/w) of phosphorus and project a limit of detection with our current apparatus of 15 ppm (w/w). For chlorine, we observed signal from 120 ppm (w/w) and project a limit of detection of 60 ppm (w/w). 相似文献
3.
4.
Spectral analysis of the plasma produced by laser-induced breakdown was demonstrated to be an effective real-time technique for the detection of atomic constituents in gases and gas-entrained particulates. The time-integrated technique, LIBS (laser-induced breakdown spectroscopy), was applied to the detection of sodium and potassium in a coal gasifier product stream, of airborne beryllium, and of phosphorus, sulfur, and chlorine in various organic molecules. In a companion paper (following) the time-resolved technique will be discussed. 相似文献
5.
《Journal of Coordination Chemistry》2012,65(9):1639-1651
Assemblies between pseudo-enantiomers with different d8 metal centers, Δ-[M(bpy){Co(aet)2(R-pn)}]3+ (M?=?Pd or Pt, bpy?=?2,2′-bipyridine, aet?=?2-aminoethanethiolate, pn?=?1,2-propanediamine), and Λ-[M′(bpy){Co(aet)2(S-pn)}]3+ (M′ ≠ M, M′?=?Pd or Pt), have been examined from stereo- and spectrochemical aspects. A mixture of equimolar amounts of the optically active sulfur-bridged dinuclear complex, Δ-[M(bpy){Co(aet)2(R-pn)}](NO3)3·7H2O, and its pseudo-enantiomer, Λ-[M′(bpy){Co(aet)2(S-pn)}](NO3)3·7H2O, in H2O crystallizes as [M(bpy){Co(aet)2(R-pn)}][M′(bpy){Co(aet)2(S-pn)}](NO3)6·4H2O, in which two complex cations with imperfect enantiomorphisms form a 1?:?1 π–π stacked unit. 相似文献
1