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1.
The electrical conductivities of aqueous solutions of NaCF3SO3, KCF3SO3, and Ni(CF3SO3)2 have been measured at 25‡C in the concentration range 1 to 25X 10-3 mol-dm-3 The data approach the Onsager limiting law at low concentrations, leading to a limiting molar ion conductivity for the CF3SO
3
−
ion of 44.5±0.2 S-cm2-mol-1, based on standard values for the cations. Using a simple size parameter for unsymmetrical polyatomic ions, based on the
ion geometry, it is shown that the well known empirical relation between the molar conductivities of symmetrical ions and
their radii can be extended to include certain polyatomic anions including CF3SO
3
−
. The results suggest that the CF3SO
3
−
ion is either a weak structure breaker in aqueous solution or neutral in this respect. 相似文献
2.
The novel bis(cyclohexylaminium) cyclohexylaminebis(orotate–N,O)cuprate(II) dihydrate, (C6H15N)2[Cu(C5H2N2O4)2(C6H14N)] · 2H2O, has been prepared and characterized by elemental analysis, magnetic measurements, FT-IR and UV–Vis spectroscopy, thermal analysis and X-ray diffraction. The Cu(II) complex crystallizes in the monoclinic space group P21/c. The copper atom in the five-coordinated (chaH)2[Cu(HOr–N,O)2(cha)] · 2H2O is chelated by a deprotonated pyrimidine nitrogen atom and carboxylate oxygen atom as a bis(bidentate) ligand and the cyclohexylamine ligand completes the square-pyramidal coordination. The thermal decomposition of the complex has been predicted by the help of thermal analysis (TG, DTG and DTA). 相似文献
3.
Several reactions of 2-naphthol with 2-alkyl-2-hydroxymethylaldehydes have been investigated. Novel synthesis of 14-(hydroxymethyl)alkyldibenzo[a,j]xanthenes and 3,3-dimethyl-4-(2-hydroxy-1-naphthyl)benzo[f]chroman has been realized. 相似文献
4.
Biphenylcarboxylic acid derivatives, and some tetracyclic bridge cycloadducts have been prepared by Diels-Alder reactions of acetylenic and olefinic dienophiles with 4-hydrpxy-6-phenyl-2H-pyran-2-one and its methyl ether derivative. 相似文献
5.
Nonmetal cation (NMC) pentaborate structures were synthesized using the amino acid molecules as cations precursors. Chemical composition analysis, infrared spectroscopy, mass analysis, boron nuclear magnetic resonance, and thermal gravimetric analysis (TGA/DTA) methods were used for structural characterization. The hydrogen storage efficiency of molecules was also determined experimentally. The recorded infrared spectra support the structural similarities of the molecules. Stretchings of pentaborate rings and characteristic peaks of amino acids were detected in infrared spectra. When the thermal analysis curves were recorded, it was found that the structures showed similar decomposition steps. Due to the result of thermal decay, glassy boron oxide (B2O3) formation was observed as the final decomposition products of all molecules. Peaks associated with boric acid, triborate, and pentaborate were observed in the 11B spectra of these salts. Powder X-ray diffraction spectroscopy supports the presence of BO3 and BO4− groups regarding the presence of pentaborate rings. It also indicates the high crystallinity of the structures. The molecular cavities detected by brunauer–emmett–teller analysis were found to be 3.586, 1.922, 1.673, and 1.923 g/cm3. Low-molecular cavities can be attributed to the high hydrogen-bonding capacity of the structures. The hydrogen capture efficiency of the pentaborate salts was found to be in the range of 0.039-0. 相似文献
6.
We study the Schrödinger equation with potentials admitting quasinormal modes using the asymptotic iteration method (AIM). We also study non-Hermitian PT symmetric potentials using AIM. The spectra, in all cases, are found to be in excellent agreement with exact results. 相似文献
7.
Fac‐bis(ethanolamine)orotatonickel(II), [Ni(HOr)(ea)2] and mer‐bis(ethanolamine)orotatocopper(II) dihydrate, [Cu(HOr)(ea)2]· 2H2O were synthesized and characterized by elemental analysis, FT‐IR, UV‐Vis Spectroscopy and thermal analysis. In addition, their solid‐state structures were determined by single crystal X‐ray diffraction studies. Both the fac‐[Ni(HOr)(ea)2] (1) and mer‐[Cu(HOr)(ea)2]·2H2O (2) complexes are isomorphous and crystallize in the triclinic space group . The Ni2+ and Cu2+ ions are coordinated by two neutral ea ligands and one orotate dianion in a distorted octahedral fashion. The ea ligand acts as a bidentate donor through the amine N and hydroxyl O atoms, while orotate dianion is coordinated through deprotonated N3 pyrimidine atom and carboxylate oxygen atom as a bidentate ligand. Thermal decompositions of the complexes are studied in over the range 20–600 °C on heating in a static air atmosphere. 相似文献
8.
Ahmet Bulut brahim Uar Okan Zafer Yeilel Hasan budak Halis
lmez Orhan Büyükgüngr 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(10):m526-m528
The title mononuclear [Cu(sq)(phen)2]·3H2O complex [sq is squarate (C4O4) and phen is 1,10‐phenanthroline (C12H8N2)] has been synthesized and the structure consists of a neutral mononuclear [Cu(sq)(phen)2] unit and three solvate water molecules. The CuII ion has distorted square‐pyramidal coordination geometry, comprised of one carboxylate O atom from a monodentate squarate ligand and four N atoms from two chelating phen ligands. An extensive three‐dimensional network of OW—H⋯O/OW hydrogen bonds, face‐to‐face π–π interactions between the 1,10‐phenanthroline aromatic rings and a weak π–ring interaction are responsible for crystal stabilization. 相似文献
9.
?lkay Çayl?Güne? Süheyla Kürkçüo?lu Okan Zafer Ye?ilelOnur ?ahin Orhan Büyükgüngör 《Polyhedron》2012,31(1):386-394
Three new heterometallic complexes, [Cu(N-Meim)4Pd(μ-CN)2(CN)2]n (1), [Zn(N-Meim)3Pd(μ-CN)2(CN)2]n (2) and [Cd(N-Meim)2Pd(μ-CN)4]n (3), have been isolated from the reactions of M[Pd(CN)4] (M = Cu(II), Zn(II) or Cd(II)) and N-Meim (N-methylimidazole) with in different molar ratios. All complexes have been characterized by X-ray analyses, vibrational (FT-IR and Raman) spectra, thermal and elemental analyses. The crystallographic analysis reveals that the crystal structures of 1 and 2 are 1D coordination polymer, while 3 presents a 2D network. In the Cu(II) and Zn(II) complexes, two cyanide groups of [Pd(CN)4]2− coordinated to the adjacent M(II) ions and distorted octahedral and square pyramidal geometries of complexes are completed by four and three nitrogen atoms of N-Meim ligands, respectively. The Cd(II) ion is six-coordinate, completed with the two nitrogen atoms of N-Meim ligands in the axial positions and the four nitrogen atoms from bridging cyano groups in the equatorial plane. The most striking features of complexes 1-3 are the presence of obvious C-H?Pd hydrogen-bonding interactions between the Pd(II) and hydrogen atoms of N-Meim ligand. This weak hydrogen bonding plays a crucial role in the architecture of the network polymers. The adjacent chains are held together by C-H?Pd, C-H?π or π?π interactions, forming three-dimensional network. 相似文献
10.
Moamen S. Refat Lamia A. El-Zayat Okan Zafer Yeşilel 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2010,75(2):745-752
Electron donor–acceptor interaction of morpholine (morp) with chloranilic acid (cla) and picric acid (pa) as π-acceptors was investigated spectrophotometrically and found to form stable charge-transfer (CT) complexes (n–π*) of [(Hmorp)2(cla)] and [(Hmorp)(pa)]2. The donor site involved in CT interaction is morpholine nitrogen. These complexes are easily synthesized from the reaction of morp with cla and pa within MeOH and CHCl3 solvents, respectively. 1HNMR, IR, elemental analyses, and UV–vis techniques characterize the two morpholinium charge-transfer complexes. Benesi–Hildebrand and its modification methods were applied to the determination of association constant (K), molar extinction coefficient (?). The X-ray crystal structure was carried out for the interpretation the predict structure of the [(Hmorp)(pa)]2 complex. 相似文献