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61.
Multi-layered thin films, which consisted of metallic silver, GeSe3 glass, and silver oxyhalide superionic conductor glass were prepared. Photo- and electrochemical reaction of metallic silver with the chalcogenide glass layer was studied by optical absorbance and cyclic-voltammetry. Photo-doping of silver through the superionic glass layer was observed using evaporated AgI---Ag2MoO4 film and it was partly undoped by electrochemical treatment. However, no photo-doping was observed for the cell consisting of a AgI---AgPO3 dip-coated layer. The doped silver was dissolved into the GeSe3 layer during the photo-doping process. However, it formed another intermediate compound layer (probably silver selenide) during the electrodoping process. 相似文献
62.
63.
N2-broadening coefficients have been measured for 41 transitions of PH3 at −100 °C in the QR branch of the ν2 band and the PP, RP, and SP branches of the ν4 band, using a tunable diode-laser spectrometer. The recorded lines with J values ranging from 1 to 13 and K from 0 to 10 are located between 1026 and 1093 cm−1. The collisional widths are determined by fitting each spectral line with a Voigt profile, a Rautian profile, and a speed-dependent Rautian profile. The latter models provide larger broadening coefficients than the Voigt model. These coefficients have also been calculated on the basis of a semiclassical model of interacting linear molecules by considering an atom-atom Lennard-Jones potential in addition to the electrostatic contributions. By comparing broadening coefficients at room and low temperatures, the temperature dependence of these broadenings has been determined both experimentally and theoretically. 相似文献
64.
Development of unique strategies to overcome Shockley–Queisser (SQ) limit in solar cells has gained a great deal of interest. Multiple exciton generation (MEG) process has been considered as one of the best approaches to the SQ limitation. In this respect, PbSe quantum dots (QDs) and nanorods (NRs) have been regarded as promising solar energy harvesting materials owing to their noticeable MEG yields. Although air stability has been regarded as one of the main disadvantage of PbSe QDs, no study has pointed out to the air sensitivity of PbSe NRs yet. Here, we reveal the effect of aspect ratio on air sensitivity and optical properties of PbSe NRs and discover that NRs with higher aspect ratios are more air stable, attributed to the reduced density of NR ends with air sensitive {100} facets. Furthermore, a band offset was created by utilization of tetrabutylammonium iodide and 1,2-ethanedithiol ligands in cell designs. We found that solar cells based on pristine PbSe NRs are limited by low open circuit voltages due to leakage current pathways. On the other hand, modified cells comprising light absorbing layers prepared by blending NRs and QDs and hole transporting QD layer exhibit a 10-fold improvement in solar cell efficiency. 相似文献
65.
Benjamin M. Gray Andrew L. Hector William Levason Gillian Reid Michael Webster Wenjian Zhang Marek Jura 《Polyhedron》2010
The reaction of o-C6H4(AsMe2)2 with VCl4 in anhydrous CCl4 produces orange eight-coordinate [VCl4{o-C6H4(AsMe2)2}2], whilst in CH2Cl2 the product is the brown, six-coordinate [VCl4{o-C6H4(AsMe2)2}]. In dilute CH2Cl2 solution slow decomposition occurs to form the VIII complex [V2Cl6{o-C6H4(AsMe2)2}2]. Six-coordination is also found in [VCl4{MeC(CH2AsMe2)3}] and [VCl4{Et3As)2]. Hydrolysis of these complexes occurs readily to form vanadyl (VO2+) species, pure samples of which are obtained by reaction of [VOCl2(thf)2(H2O)] with the arsines to form green [VOCl2{o-C6H4(AsMe2)2}], [VOCl2{MeC(CH2AsMe2)3}(H2O)] and [VOCl2(Et3As)2]. Green [VOCl2(o-C6H4(PMe2)2}] is formed from [VOCl2(thf)2(H2O)] and the ligand. The [VOCl2{o-C6H4(PMe2)2}] decomposes in thf solution open to air to form the diphosphine dioxide complex [VO{o-C6H4(P(O)Me2)2}2(H2O)]Cl2, but in contrast, the products formed from similar treatment of [VCl4{o-C6H4(AsMe2)2}x] or [VOCl2{o-C6H4(AsMe2)2}] contain the novel arsenic(V) cation [o-C6H4(AsMe2Cl)(μ-O)(AsMe2)]+. X-ray crystal structures are reported for [V2Cl6{o-C6H4(AsMe2)2}2], [VO(H2O){o-C6H4(P(O)Me2)2}2]Cl2, [o-C6H4(AsMe2Cl)(μ-O)(AsMe2)]Cl·[VO(H2O)3Cl2] and powder neutron diffraction data for [VCl4{o-C6H4(AsMe2)2}2]. 相似文献
66.
67.
Jonathan P. Blitz Nigel T. Lucas Mark G. Humphrey 《Journal of organometallic chemistry》2002,650(1-2):133-140
The 60-electron tetrahedral clusters W2Ir2(μ-L)(CO)8(η5-C5H4Me)2 [L=dppe (2), dppf (3)] have been prepared from reaction between W2Ir2(CO)10(η5-C5H4Me)2 (1) and the corresponding diphosphine in 52 and 66% yields, respectively. A structural study of 2 reveals that three edges of a WIr2 face are spanned by bridging carbonyls, that the iridium-ligated diphosphine coordinates diaxially and that the tungsten-bound methylcyclopentadienyls coordinate axially and apically with respect to the plane of bridging carbonyls. A structural study of 3 reveals that the dppf ligand bridges an Ir---Ir bond which is also spanned by a bridging carbonyl; tungsten-ligated methylcyclopentadienyl ligands and terminal carbonyls result in electronic asymmetry (17e and 19e iridium atoms) in the electron-precise cluster. Both clusters show two reversible one-electron oxidation processes and an irreversible two-electron reduction; the dppf-containing cluster 3 has a further, irreversible, one-electron oxidation process. UV–vis-NIR spectroelectrochemical studies of the 2→2+→22+ progression reveal the appearance of a low-energy transition on oxidation to 2+ which persists on further oxidation to 22+. 相似文献
68.
Suman Gomosta Rongala Ramalakshmi Chinnappa Arivazhagan Anagha Haridas Beesam Raghavendra Kuppaiyandi Maheswari Thierry Roisnel Sundargopal Ghosh 《无机化学与普通化学杂志》2019,645(6-7):588-594
The complexes [Ag{κ3‐S,S′,H‐H2B(mbz)2}(PR3)]x, ( 1 : x = 2, R = Ph; 2 : x = 1, R = Cy) (mbz = 2‐mercaptobenzothiazolyl) and amidine based dihydro(2‐mercaptobenzo‐thiazolyl) borates, [HN=C(Ph)–NH(R)–H2B(mbz)] ( 3 : R = 2,6‐diisopropylphenyl and 4 : R = Ph) were synthesized and characterized by various spectroscopic methods and single‐crystal X‐ray crystallography. Complex [Ag{κ3‐S,S′,H‐H2B(mbz)2}(PPh3)]2 ( 1 ) has a dimeric structure in its crystalline state, in which central silver(I) atoms adopt a distorted trigonal bipyramid arrangement. In contrast, complex [Ag{κ3‐S,S′,H‐H2B(mbz)2}(PCy3)] ( 2 ) has a monomeric structure in its crystalline state, in which the central silver(I) atoms adopt a distorted trigonal planar arrangement. Infrared spectroscopy was utilized as a tool for investigating the presence of M ··· H–B interactions. In addition, density functional theory (DFT) calculations were used to analyse the B–H ··· [M] bonding interaction in the metal borate complexes. 相似文献
69.
In situ-generated (bis-DPPMB)-Cu(OTf)2 complex has been examined to catalyze a tandem olefin migration and Prins cyclization of an alkenol with various aldehydes. The reaction proceeded with electron-rich aromatic aldehydes at room temperature and provided functionalized tetrahydropyrans in good yields. An efficient synthesis of the bis-DPPMB ligand has also been described. 相似文献
70.
《Journal of Coordination Chemistry》2012,65(4):679-687
Cationic nickel(II) complexes containing chelating O,O′-donor maltolate or ethyl maltolate ligands in conjunction with bidentate bisphosphine ligands Ph2P(CH2) n PPh2 were prepared by a one-pot reaction starting from nickel(II) acetate, bisphosphine, maltol (or ethyl maltol), and trimethylamine, and isolated as their tetraphenylborate salts. An X-ray structure determination of [Ni(maltolate)(Ph2PCH2CH2PPh2)]BPh4 shows that the maltolate ligand binds asymmetrically to the (slightly distorted) square-planar nickel(II) center. The simplicity of the synthetic method was extended to the synthesis of the known platinum(II) maltolate complex [Pt(maltolate)(PPh3)2]BPh4 which was obtained in high purity. 相似文献