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201.
Two-weight codes and projectivesets having two intersection sizes with hyperplanes are equivalentobjects and they define strongly regular graphs. We construct projective sets in PG(2m – 1,q) that have the sameintersection numbers with hyperplanes as the hyperbolic quadricQ+(2m – 1,q). We investigate these sets; we provethat if q = 2 the corresponding strongly regular graphsare switching equivalent and that they contain subconstituentsthat are point graphs of partial geometries. If m = 4the partial geometries have parameters s = 7, t = 8, = 4 and some of them are embeddable in Steinersystems S(2,8,120). 相似文献
202.
采用密度泛函理论的B3LYP方法,获得了BenLi(n=1~12)掺杂团簇的基态结构.同时计算相应的平均结合能、离解能、能量二阶有限差分和能隙.结合最高分子占据轨道的电子密度分析了掺杂团簇的成键特性,并与单一组元的BeN(N=2~13)团簇进行对比.结果表明n=4和9是团簇的幻数;随着尺寸n的增加,BenLi团簇中Be-Li间的相互作用由类共价键过渡到类离子键. 相似文献
203.
Darren Crowdy 《International Journal of Non》2011,46(4):577-585
The motion of a circular treadmilling low Reynolds number swimmer near a no-slip wall is studied analytically. First, the exact solution of Jeffrey and Onishi [Q. J. Mech. Appl. Math., 34 (1981)] for a translating and rotating solid cylinder near a no-slip wall is rederived using a novel conformal mapping approach that differs from the original derivation which employed bipolar coordinates. Then it is shown that this solution can be combined with the reciprocal theorem, and the calculus of residues, to produce an explicit non-linear dynamical system for the treadmilling swimmer's velocity and angular velocity. The resulting non-linear dynamical system governing the swimmer motion is used to corroborate the qualitative results obtained by an approximate model of the same swimmer recently presented in Crowdy and Or [Phys. Rev. E., 81 (2010)]. 相似文献
204.
205.
Ringo Rey‐Villaverde Hubert Cybulski Jesús R. Flores Berta Fernández 《Journal of computational chemistry》2013,34(23):2020-2031
We have performed high‐level electronic structure computations on the most important species of the CHnP systems n = 1–3 to characterize them and provide reliable information about the equilibrium and vibrationally averaged molecular structures, rotational constants, vibrational frequencies (harmonic and anharmonic), formation enthalpies, and vertical excitation energies. Those chemical systems are intermediates for several important reactions and also prototypical phosphorus‐carbon compounds; however, they are often elusive to experimental detection. The present results significantly complement their knowledge and can be used as an assessment of the experimental information when available. The explicitly correlated coupled‐cluster RCCSD(T)‐F12 method has been used for geometry optimizations and vibrational frequency calculations. Vibrational configuration interaction theory has been used to account for anharmonicity effects. Basis‐set limit extrapolations have been carried out to determine accurate thermochemical quantities. Electronic excited states have been calculated with coupled‐cluster approaches and also by means of the multireference configuration interaction method. © 2013 Wiley Periodicals, Inc. 相似文献
206.
采用基于密度泛函理论的第一性原理方法,在多种初始构型下充分考虑自旋多重度,研究了BenLa团簇的平衡几何结构、电子性质和磁性.结果表明:BenLa团簇的基态附近有许多能量非常接近的同分异构体,说明该团簇结构较复杂,对其基态的寻找极具挑战性.BenLa团簇具有磁性且稳定性远高于Ben+1团簇,由此可知通过选择合适的掺杂元素可能得到高稳定性的磁性团簇.Be1
关键词:
nLa团簇')" href="#">BenLa团簇
平衡几何结构
电子性质和磁性 相似文献
207.