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91.
A new Co(III) complex of 1,2-cyclohexanedionedioxime and thiocarbamide with an SO 4 2? anion and solvation water molecules in the outer sphere has been synthesized and its structure has been defined. Orthorhombic crystals, a = 11.659(2) Å, b = 26.448(5) Å, c = 30.142(6) Å, V = 9295(3) Å 3, Z = 8, dcalc = 1.599 g/cm3, space group Pbca; final R index is 0.0578 for 8221 reflections with I > 2σ(I). In the octahedral Co(III) complex, two 1,2-cyclohexanedionedioxime residues lie in the equatorial plane, while two thiocarbamide molecules are in the axial plane. Intramolecular bonds: N-H…O and O-H…O type hydrogen bonds and π-π interactions that stabilize the complex cations. In crystal, the components are linked by N-H…O and O-H…O hydrogen bonds into a 3D framework.  相似文献   
92.
Two novel coordination compounds of thiourea-containing trans-octahedral trans-dioximates of trivalent cobalt [Co(DH)2(Tu)2]2[ZrF6]·H2O and [Co(NioxH)2(Tu)2]2[ZrF6]·3H2O, where DH? is the monoanion of dimethylglyoxime, NioxH? is the monoanion of 1,2-cyclohexanone dioxime, Tu is thiourea, are prepared and characterized by single crystal X-ray diffraction. The structures manifest pairwise an almost parallel and perpendicular arrangement of the Tu fragment in respect to the equatorial plane of the coordination core, accompanied by a development of non-bonding intramolecular π-π-and N-H...O-interactions affecting the structures of the compounds in question. The formation of the crystal structures is primarily governed by outer-sphere [ZrF6]2? anions and crystallization water molecules.  相似文献   
93.
The molecular structure of a series of homo- and copolyesters was studied using sustained off-resonance irradiation collisionally activation dissociation on a Fourier transform ion cyclotron resonance mass spectrometer. Electrospray ionization was used as an ionization technique. The most important fragmentation pathways of the homopolyesters poly(dipropoxylated bisphenol-A/adipic acid) and poly(dipropoxylated bisphenol-A/isophthalic acid) were studied. Six different dissociation mechanisms were observed which are very similar to the mechanisms found to occur during pyrolysis of these compounds. Four of these mechanisms are a result of cleavages of the ester bond and the others are due to cleavages of the ether bond or bisphenol-A unit. Some of the fragments expected are not present in the spectrum, indicating that each fragment has a specific sodium affinity. Sequence-specific fragments of two of the three copolyester sequences that theoretically can exist were experimentally observed. Fragments that originate from the third sequence are not unique and can also be formed from other sequences. Therefore, it was not possible to determine the presence of the third sequence. Copyright 2000 John Wiley & Sons, Ltd.  相似文献   
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