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81.
The crystal structure of phenothiazine-10-propionic acid, C12H8SNC2H4COOH, was determined from three-dimensional X-ray diffraction data collected with a manual diffractomer using MoKα (λ 0.71069 Å) radiation. The space group is P21/c with a = 7.888 (2)Å, b = 8.703 (2)Å, c = 19.700 (8)Å, β = 101.42 (1)°, Z = 4, Dmeas = 1.35(2) g. cm?3 and Dcalc = 1.36 g. cm?3 at 23°. The structure was determined by the direct method and refined with 500 observed reflections by full-matrix least squares to an R of 0.072. The molecule is folded along the S-N axis and the dihedral angle is 136.5°. The C-S-C angle is 98.5(7)° and the average C-S bond is 1.77(2)Å. The shortening of the C-S bond, the small value of the C-S-C angle and the folding of the molecule are typical of the phenothiazine class of compounds and are assumed to be due to sulfur d orbital participation in ring bonding. 相似文献
82.
The title compound [CpRu(PPh3)2(tht)]BF4,1, tht=tetrahydrothiophene, is obtained by the reaction of CpRu(PPh3)2Cl, tht and AgBF4 in CH2Cl2 solution. Yellow crystals of [CpRu(PPh3)2(tht)]BF4 were grown by the slow diffusion of pentane into a CH2Cl2 solution of1 and have been studied by X-ray crystallography: space group is P21/n,a=9.507(2),b=18.336(3),c=22.372(6) Å, =94.28(2)°,V=3889(1) Å3,Z=4. The tht ligand binds to the Ru atom through the sulfur atom at a distance of 2.395(2) Å. The tht ring is in the puckered configuration. 相似文献
83.
William M. Willingham John R. J. Sorenson Faith Yarberry Wally Cordes 《Journal of chemical crystallography》1993,23(6):505-507
Crystals oftrans-aqua-bis(pyridine)dibenzoatocopper(II), Cu(NC5H5)2(C7H5O2)2(H2O), are monoclinic,P21/n, witha=5.9847(10),b=18.874(5),c=19.728(10)A,=92.97(4)°,Z=4, andV=2225.5(13)A3. The full-matrix least-squares refinement used 3030 reflections withI> 2.5(I) and converged toR=0.067. The benzoate ions bond as monodentate ligands in this five-coordinate complex. The copper ion is in a square pyrimidal environment with trans pyridine groups and benzoate ions in a slightly distorted square planar arrangement and a water ligand in the axial position. The Cu-O distance to the water molecule is significantly longer (2.273(4) Å) than the distances to the O atoms of the carboxyl groups (1.934(3) and 1.930(4)Å). 相似文献
84.
Craig A. Johnston David B. Cordes Tomas Lebl Alexandra M. Z. Slawin Nicholas J. Westwood 《Molecules (Basel, Switzerland)》2021,26(19)
The bioactive natural product perophoramidine has proved a challenging synthetic target. An alternative route to its indolo[2,3-b]quinolone core structure involving a N-chlorosuccinimde-mediated intramolecular cyclization reaction is reported. Attempts to progress towards the natural product are also discussed with an unexpected deep-seated rearrangement of the core structure occurring during an attempted iodoetherification reaction. X-ray crystallographic analysis provides important analytical confirmation of assigned structures. 相似文献
85.
X.R. WU M. Hirsch A. Staudt H.V. Klapdor-Kleingrothaus Cheng-Rui CHING Tso-Hsiu HO 《理论物理通讯》1993,20(4):453-460
The half-lives for 2νββ decay for all the potential Pp-emitters with A≥70 are calculated by the operator expansion method. Compared with the directly measured half-lives of 76Ge, 82Se, 100Mo and 238U the theoretical values are in excellent agreement with experimental ones. 相似文献
86.
A new method-the operator expansion method is used in neutrinoless double beta decay processes. Both the neutrino mass and mixing of right-handed leptonic current are included. It is shown that for nuclear neutrinoless double beta decay in 2n mechanism, there appear some new terms besides the terms given by the conventional treatment based on closure approximation. The ββ with a Majoron emission is also discussed. 相似文献
87.
We discuss the problem of microcausality in a model of quantized field theory. Under the assumptions that the commutator of the "in" fields satisfies the requirement of translational invariance, we show that, in the case of self-conjugate scalar particles or particles with integer spins, one can deduce the law of microcausality. 相似文献
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