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81.
《Journal of Coordination Chemistry》2012,65(21):3776-3791
Three triphenyltin chloride complexes, [(Ph3SnCl)2?·?(bpy)1.5] (1), [(Ph3SnCl)2.tbpe] (2), and [(Ph3SnCl)2?·?bpe] (3), were synthesized by reaction of triphenyltin chloride with 4,4′-bipyridine (bpy), trans-1,2-bis(4-pyridyl)ethylene (tbpe), and 1,2-bis(4-pyridyl)ethane (bpe) in water/acetonitrile. Both 2 and 3 are binuclear; each consists of two Ph3SnCl molecules bridged by the bidentate ligand. Complex 1 consists of two crystallographically independent and chemically different coordination complexes, mononuclear and binuclear in equal proportion. The structures of these complexes were investigated by single-crystal X-ray analysis, elemental analyses, NMR spectroscopy as well as electronic absorption and emission spectroscopy. The three complexes exhibit in vitro antitumor activity against human breast cancer cell line, MCF7. 相似文献
82.
《Journal of Coordination Chemistry》2012,65(7):571-577
A direct synthetic method of mixing Bi(NO3)3 and NaI with 1,10-phenanthroline yielded red crystals of [Bi2(phen)4(NO3)4.4I0.6]I3. In this complex the cationic part is in fact binuclear and contains two [Bi(phen)(NO3)1.7I0.3] groups linked via a bridging NO? 3 anion. The I? 3 anion was not coordinated to bismuth(III) and the lone pair of valence electrons of the bismuth(III) ions appears to be stereochemically inactive. There are two independent NO? 3 anions, one coordinated to bismuth but another shares a position with I? anion. The final results of crystallography show that 40% of these positions are occupied by NO? 3 anions and 60% by I? anions that are coordinated to bismuth atom in bidentate fashion (NO? 3) and in unidentate fashion (I?). An interesting point is that the I? 3 anion was produced by direct synthetic method (Branched tube method). There is a π-π stacking interaction between the parallel aromatic rings around the Bi(III) ion. 相似文献
83.
根据对应原理,得到了类氢原子能态平均寿命半经典的计算公式τ(n,l),然后利用相对论单通道量子数亏损理论进行推广,得到用来计算考虑总角动量J的激发态寿命公式τ(n,l,l+1/2)和τ(n,l,l-1/2),利用单通道量子数亏损理论得到了碱金属原子n、l远大于1时激发态寿命的半经典公式τ(n.l)=τ0(m+M/nm/v/+M)2v7l(l+1/2)/n4,其计算结果和实验数据符合的很好. 相似文献
84.
The paramagnetic center of tetragonal symmetry formed by the Yb3+ ion in the KZnF3 crystal has been studied using methods of EPR, ENDOR and optical spectroscopy. The location of the impurity ion and the structural model of the complex differing from the model of the Yb3+ center in KMgF3 have been established. The empirical scheme of the energy levels of the Yb3+ ion has been found. The parameters of its interaction with the crystal electrostatic field and the hyperfine interaction with ligands of the nearest environment have been determined. The parameters of the crystal field were used for the analysis of the distortions of the crystal lattice in the vicinity of Yb3+. The parameters of the transferred hyperfine interaction have been calculated for the distances between Yb3+ and F− ions of the nearest environment obtained taking into account the found distortions. They are in good agreement with the experimental values. 相似文献
85.
86.
87.
In this work, we reported the effect of Li2CO3 addition on the structural, optical, ferroelectric properties and electric-field-induced strain of Bi0.5(Na,K)0.5TiO3 (BNKT) solid solution with CaZrO3 ceramics. Both rhombohedral and tetragonal structures were distorted after adding Lithium (Li). The band gap values decreased from 2.91 to 2.69 eV for 5 mol% Li-addition. The maximum polarization and remanent polarization decreased from 49.66 μC/cm2 to 27.11 μC/cm2 and from 22.93 μC/cm2 to 5.35 μC/cm2 for un-doped and 5 mol% Li- addition BNKT ceramics, respectively. The maximum Smax/Emax value was 567 pm/V at 2 mol% Li2CO3 access. We expected this work will help to understand the role of A-site dopant in lead-free ferroelectric BNKT materials. 相似文献
88.
Abstract The symmetric 'end-off' compartmental proligand 2,6-[N,N′-bis(2-hydroxy-phenylmethyl)-N,N′-bis(2-pyridylmethyl)aminomethyl]-4-methylphenol (H3L) has been used to generate homodinuclear nickel(II) and zinc(II) complexes. The crystal structures of the complexes reveal that the di-nickel(II) complex is donor asymmetric and the di-zinc(II) complex is coordination number asymmetric. In both complexes non-coordinated acetic acid molecules are tightly hydrogen-bonded to the pendant phenols of the ligand generating a double acid salt of the type[CH3COO…H…L…H…OOCCH3]3? in the dinickel complex and a single acid salt of the type [CH3COO…H…L]3? in the dizinc complex. In both cases the ligand periphery has been extended to provide a supraligand in which the donor potential of the original ligand has been enhanced. 相似文献
89.
Lan-Hua Wei Yong-Bing He Jin-Long Wu Xiao-Jun Wu Ling-Zhi Meng Xi Yang 《Supramolecular chemistry》2013,25(8):561-567
Two colorimetric thiourea-based chemsensors with two relatively rigid arms, 2A and 2B, were synthesized. Their binding abilities with halide anions, AcO?, [Formula: See Text] were studied by UV-Vis spectroscopy in DMSO. The two sensors showed a notable selective color response to F? anion from colorless to green-yellow in recognition. The structures of the two sensors and their binding behaviors are discussed. The association constants were calculated by nonlinear fittings of 1:1, 1:2 or 1:1 to 1:2. 相似文献
90.
《合成通讯》2013,43(24):3865-3869
ABSTRACT Three bisthiocarbohydrazones had been synthesized and characterized. The structures of the three compounds were determined by elemental analysis, IR, MS, 1H NMR and 13C NMR. The crystal structure of one of the compounds was determined by X-ray single crystal diffraction techniques. 相似文献