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61.
采用不可约张量法,分析了KTbP4O12晶体荧光光谱,拟合了五个晶场参量和八个相对论参量,结果与实验吻合。 相似文献
62.
Unrestricted Hartree-Fock calculations with large basis sets, including d-functions, and the estimation of the correlation energy, show that the potential energy surface for the Li-CO2 complex is built from the crossing of two states, each of them corresponding to a different electron arrangement. One has a strong ionic character and the other is of van der Waals type. Each portion of the energy surface presents a minimum, which is stable in respect to the dissociation limit. 相似文献
63.
A Metal–Organic Framework with Cooperative Phosphines That Permit Post‐Synthetic Installation of Open Metal Sites 下载免费PDF全文
Samuel G. Dunning Gianne Nandra Adam D. Conn Wenrui Chai R. Eric Sikma Ji Sun Lee Pranaw Kunal Joseph E. Reynolds III Jong‐San Chang Alexander Steiner Graeme Henkelman Simon M. Humphrey 《Angewandte Chemie (International ed. in English)》2018,57(30):9295-9299
PCM‐101 is a phosphine coordination material comprised of tris(p‐carboxylato)triphenylphosphine and secondary pillaring groups coordinated to [M3(OH)]5+ nodes (M=Co, Ni). PCM‐101 has a unique topology in which R3P: sites are arranged directly trans to one another, with a P???P separation distance dictated by the pillars. Post‐synthetic coordination of soft metals to the P: sites proceeds at room temperature to provide X‐ray quality crystals that permit full structural resolution. Addition of AuCl groups forces a large distortion of the parent framework. In contrast, CuBr undergoes insertion directly between the trans‐P sites to form dimers that mimic solution‐phase complexes, but that are geometrically strained due to steric pressure exerted by the MOF scaffold. The metalated materials are active in heterogeneous hydroaddition catalysis under mild conditions, yielding different major products compared to their molecular counterparts. 相似文献
64.
The potential energy surface for the decomposition of HXSiS (X = H, F, and Cl) on the singlet state has been explored by B3LYP and CCSD(T) calculations. Five different types of reaction are proposed: (A) 1,1‐HX elimination, (B) 1,2‐H shift, (C) 1,2‐X shift, (D) H · and XSiS · radical formation, and (E) X · and HSiS · radical formation. These results show interesting trends for the HXSiS isomers. Our theoretical investigations suggest that the doubly bonded species HXSiS should be the lowest energy structure among the isomers from both kinetic and thermodynamic viewpoints. We also report theoretical predictions of molecular parameters and vibrational infrared (IR) spectra of the monohalogen‐substituted silanethione, which should be useful for future experimental observations. © 2001 John Wiley & Sons, Inc. Int J Quant Chem 82: 14–25, 2001 相似文献
65.
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67.
The relation and transformation between hierarchical inner product encryption and spatial encryption
Hierarchical inner product encryption (HIPE) and spatial encryption (SE) are two important classes of functional encryption that have numerous applications. Although HIPE and SE both involve some notion of linear algebra, the former works in vectors while the latter is based on (affine) spaces. Moreover, they currently possess different properties in terms of security, anonymity (payload/attribute-hiding) and ciphertext sizes, for example. In this paper, we formally study the relation between HIPE and SE. In our work, we discover some interesting and novel property-preserving transformation techniques that enable generic construction of an SE scheme from an HIPE scheme, and vice versa. 相似文献
68.
The algebraic category is the image of MV, the category whose objects are the MV‐algebras, by the equivalence (cf. 7 , 8 ). In this paper we define the logic ?? whose Lindenbaum algebra is an MV‐algebra (object of ), and establish a link between ?? and the infinite valued ?ukasiewicz logic ?. We define U‐operators, that have properties of universal quantifiers, and establish a bijection that maps an MV‐algebra endowed with a U‐operator (cf. 20 - 22 ) into an MV?‐algebra endowed with a U‐operator. This map extends to a functor that is a categorical equivalence. 相似文献
69.
LetA be a finite dimensional commutative semisimple algebra over a fieldk and letV be a finitely generatedA-module. We examine the action of the general linear group GL
A
(V) on the set of flags ofk-subspaces ofV. Also, let (V, B) be a finitely generated symplectic module overA. We also investigate the action of the symplectic group Sp
A
(V, B) on the set of flags ofB-isotropick-subspaces ofV, whereB=°B is thek-symplectic form induced by a nonzerok-linear map :A k. In both cases, the orbits are completely classified in terms of certain integer invariants provided that dim
k A=2.This work is partially supported by a KOSEF research grant. 相似文献
70.
We determine the structure of cyclic codes over
for arbitrary even length giving the generator polynomial for these codes. We determine the number of cyclic codes for a
given length. We describe the duals of the cyclic codes, describe the form of cyclic codes that are self-dual and give the
number of these codes. We end by examining specific cases of cyclic codes, giving all cyclic self-dual codes of length less
than or equal to 14.
San Ling - The research of the second named author is partially supported by research Grants MOE-ARF R-146-000-029-112 and
DSTA R-394-000-011-422. 相似文献