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11.
Stanko Tomi Tomah Sogabe Yoshitaka Okada 《Progress in Photovoltaics: Research and Applications》2015,23(5):546-558
Coupled semiconductor quantum dot (QD) arrays emerged recently as promising structures for the next generation of high efficiency intermediate band solar cell (IBSC), because of their ability to facilitate the formation of minibands. The quantum coupling effect that exists between states in QDs in an array influences the electronic and optical properties of such structures. So far, great experimental and theoretical efforts have been devoted to study the vertically coupled QD arrays. We present here a method based on multi‐band k ⋅ p Hamiltonian combined with periodic boundary conditions, applied to predict the electronic and optical properties of InAs/GaAs QDs‐based lateral QD arrays. Formation of the intermediate band (IB) in all cases was achieved via delocalisation of the electron ground state (e0). We show that the IB in a laterally coupled QD‐IBSC is more robust against external electric field from the solar cell's pn junction than that in a vertically coupled arrangement. Because of symmetry of the QD array lattice and QD states itself, which are C2v for the zinc blend QDs, the electronic and absorption structures were obtained via sampling throughout the reciprocal space in the first Brillouin zone of QD arrays. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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From the reaction of 1‐HOCPh2‐2‐NMe2C6H4 ( 1 ), 1‐HOC(C6H11)2‐2‐NMe2C6H4 ( 2 ) and 1‐HOCPh2CH2‐2‐NMe2C6H4 ( 3 ) with n‐BuLi in diethyl ether, the solvent‐free chelated dimethylamino lithium alkoxides [1‐LiOCPh2‐2‐NMe2C6H4]2 ( 4 ), [1‐LiOC(C6H11)2‐2‐NMe2C6H4]2 ( 5 ) and [1‐LiOCPh2CH2‐2‐NMe2C6H4]2 ( 6 ) were obtained. The lithium alkoxides 4 – 6 were characterized by 1H, 7Li, and 13C NMR spectroscopy. Crystal structure determinations of 5 and 6 were carried out. Compounds 5 and 6 are examples of structurally characterized solvent‐free chelated dimethylamino lithium alkoxides and 6 is a rare example of this type containing a seven‐membered ring. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
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Tomohiro Sogabe Takeo Hoshi Shao-Liang Zhang Takeo Fujiwara 《Journal of computational physics》2012,231(17):5669-5684
We develop the shifted COCG method [R. Takayama, T. Hoshi, T. Sogabe, S.-L. Zhang, T. Fujiwara, Linear algebraic calculation of Green’s function for large-scale electronic structure theory, Phys. Rev. B 73 (165108) (2006) 1–9] and the shifted WQMR method [T. Sogabe, T. Hoshi, S.-L. Zhang, T. Fujiwara, On a weighted quasi-residual minimization strategy of the QMR method for solving complex symmetric shifted linear systems, Electron. Trans. Numer. Anal. 31 (2008) 126–140] for solving generalized shifted linear systems with complex symmetric matrices that arise from the electronic structure theory. The complex symmetric Lanczos process with a suitable bilinear form plays an important role in the development of the methods. The numerical examples indicate that the methods are highly attractive when the inner linear systems can efficiently be solved. 相似文献
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The Conjugate Gradient (CG) method and the Conjugate Residual (CR) method are Krylov subspace methods for solving symmetric (positive definite) linear systems. To solve nonsymmetric linear systems, the Bi-Conjugate Gradient (Bi-CG) method has been proposed as an extension of CG. Bi-CG has attractive short-term recurrences, and it is the basis for the successful variants such as Bi-CGSTAB. In this paper, we extend CR to nonsymmetric linear systems with the aim of finding an alternative basic solver. Numerical experiments show that the resulting algorithm with short-term recurrences often gives smoother convergence behavior than Bi-CG. Hence, it may take the place of Bi-CG for the successful variants. 相似文献
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Synthesis and Spectroscopic Properties of PdII and PtII Complexes with Monosulfide and Monoselenide Bis(phosphanyl)amine Ligands
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Oxidation of N,N‐bis(diphenylphosphanyl)naphthalen‐1‐amine ( 1 ) with elemental sulfur or gray selenium (1:1 molar ratio) gave the corresponding monosulfide and monoselenide bis(phosphanyl)amine ligands C10H7‐1‐N(P(E)Ph2)(PPh2) [E = S ( 2 ), Se ( 3 )], respectively. Reactions of 2 and 3 with MCl2(cod) (M = Pd, Pt) afforded [MCl2{ 2 ‐κ2P,S}] [M = Pd( 4 ), Pt( 5 )] and [MCl2{ 3 ‐κ2P,Se}] [M = Pd( 6 ), Pt( 7 )], respectively. In contrast, reactions of the same ligands with NiCl2(PPh3)2 resulted in deselenization and desulfurization, producing complex 8 with the formula [NiCl2{1‐κ2P,P}]. Ligands 2 and 3 , as well as their complexes 4 – 7 and 8 were identified and characterized by multinuclear NMR (1H, 13C, 31P, and 77Se NMR) spectroscopy, elemental analysis, and IR spectroscopy. Additionally, the molecular structure of 8 was obtained. 相似文献
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The aminoalcohols 1-HOCR2-2-NMe2C6H4 [R = Ph (1), R = C6H11 (2)] and 1-HOCPh2CH2-2-NMe2C6H4 (3) react with ZnCl2 in tetrahydrofuran to give the alcohol adducts [ZnCl2(THF){1-HOCR2-2-NMe2C6H4}] [R = Ph (4), R = C6H11 (5)] and [ZnCl2(THF){1-HOCPh2CH2-2-NMe2C6H4}] (6). The complexes 4–6 were characterized by 1H and 13C NMR spectroscopy, and 5 was also structurally characterized by X-ray crystallography. 相似文献
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Dr. Harbi Tomah Al‐Masri 《无机化学与普通化学杂志》2012,638(6):1012-1017
The reaction of 1‐naphthylamine with two equivalents of chlorodiphenylphosphine in the presence of triethylamine gave the ligand C10H7‐1‐N(PPh2)2 ( 1 ). Reaction of 1 with PdCl2(CH3CN)2 or PtCl2(cod) (1:1 molar ratio) afforded the complexes cis‐[PdCl2{C10H7‐1‐N(PPh2)2}] ( 2 ) and cis‐[PtCl2{C10H7‐1‐N(PPh2)2}] ( 3 ), respectively. Compounds 1 – 3 were identified and characterized by multinuclear NMR (1H, 13C, 31P NMR) and IR spectroscopy. Crystal structure determinations of complexes 2 and 3 were carried out. 相似文献
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The reaction of C10H7-1-N(PPh2)2 ( 1 ) with two equivalents of CuI in acetonitrile resulted in the formation of octahedron Cu4I4[ 1 ]2 complex ( 2 ). The crystal structure of 2 showed it adopted a rare octahedral arrangement. The rectangular Cu4 plane is μ4-capped by two of the iodides and is placed in axial positions above and below the Cu4-plane form an octahedron, whereas the other two iodides are bonded to two copper atoms in a μ2-fashion. The luminescence of complex 2 arises from a triplet halide-to-ligand charge transfer (3XLCT) excited state and 3CC (Cu4I4 cluster-centered) excited state are not involved in the luminescence by the rigid bidentate ligand 1 in spite of the short CuI–CuI bond length. Complex 2 was identified and characterized by multinuclear NMR (1H, 13C, 31P NMR) and IR spectroscopy. Crystal structure determinations of 1 and 2 were carried out. 相似文献
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In the present paper, we give a fast algorithm for block diagonalization of k-tridiagonal matrices. The block diagonalization provides us with some useful results: e.g., another derivation of a very recent result on generalized k-Fibonacci numbers in [M.E.A. El-Mikkawy, T. Sogabe, A new family of k-Fibonacci numbers, Appl. Math. Comput. 215 (2010) 4456-4461]; efficient (symbolic) algorithm for computing the matrix determinant. 相似文献