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Using the first-principles plane-wave pseudopotential method, based on the density function theory, the electron structure and optical properties of GaAs (100) β2(2×4) and GaAs (100) (4×2) reconstructions are calculated. The formation energy of As-richβ2 (2 ×4) reconstruction is minus and the formation energy of Ga-rich (4×2) reconstruction is positive; As-rich β2(2×4) reconstruction is stable and Ga-rich (4×2) reconstruction is unstable. Ga-rich (4×2) reconstruction owns lower work function. The electrons at two reconstructions both move into the bulk and form a band-binding region. Both the absorption and the refleetivity of As-rich β2(2×4) reconstruction are smaller than the Ga-rich (4× 2) reconstruction. As- rich β2(2×4) reconstruction is more benefit for the movement of photos through the surface to emit photoelectrons. 相似文献
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在微波放电系统中,对NH_3-F-F_2-CF_3I体系进行研究,结果表明,向IF(X)传能的诸多媒介中,N_2(A)及N(~2D)起着主要作用,并且这一结论在经微波激发后的N_2与CF_3I的直接反应中得到了进一步证实。 相似文献
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在考虑NO分子的(5σ)^2(1π)^43P-(5σ)^2(1π)^3(2π)^2构形相互作用的情况下,对D^2Σ,C^2Ⅱ,B^2Ⅱ和L^2Ⅱ电子态的转动能级结构以及态函数进行了计算,计算结果与实验结果很相符。 相似文献
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一般教材中,在讨论一维弦线中的横波波动方程时,都假设弦线中的张力为恒量,在小扰动情况下,推导横波波动方程,本文在较一般情况下,推导一维弦线中的横波波动方程,并讨论弦线中张力的变化等问题,所得结果在小扰动近似下,与一般教材中的结论一致。 相似文献
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DING Xiang-Mao WANG Gui-Dong WANG Shi-Kun 《理论物理通讯》2007,47(1):69-77
Motivated by the recently discovered hidden symmetry of the type IIB Green-Schwarz superstring on certain background, the non-semisimple Kac-Moody twisted superalgebra gl(2|2)(2)k is investigated by means of the vector coherent state method and boson-fermion realization. The free field realization of the twisted current superalgebra at general level k is constructed. The corresponding Conformai Field Theory (CFT) has zero central charge. According to the classification theory, this CFT is a nonunitary field theory. After projecting out a U(1) factor and an outer automorphism operator, we get the free field representation of psl(2|2)(2)k, which is the a/gebra of gl(2|2)(2)k modulo the Z4-outer automorphism, the CFT has central charge -2. 相似文献
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采用包含库仑相关的三体近似末志波函数,计算了入射能为250eV、散射角为3°、5°、7°、9°条件下e-+H(2s)→H++2e-共面反对称三重微分散射截面(TDCS),并与三级修正的EBS结果进行了比较。结果发现基态H电离与亚稳态电离特征有很大的差别。 相似文献
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合成了标题化合物{Mn(IBG)(4,4'-bipy)(H2O)2}·(H2O)2(H2IBG =1,3-苯二甲酰二甘氨酸,4,4'-bipy=4,4'-联吡啶),并通过X-射线衍射对其单晶结构进行了测定.该结构属于三斜晶系,空间群P-1,分子量Mr=561.41,晶胞参数a=0.90278(8)nm,b=1.16584(1)nm,c=1.31133(1)nm,V=1.21309(2)nm3,Z=2,Dc=1.537g·cm-3,F(000)=582.0.由于分子间氢键,使得分子结构更趋稳定.通过红外光谱、热重分析等对化合物进行了表征. 相似文献
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