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Lawrence H.Lazarus 《中国化学快报》2011,22(8):907-910
Analogues of endomorphin and tripeptidcs modified at positions 4 and 3,respectively,with various phenylalanine analogues were synthesized and their affinities for opioid receptors were evaluated.Most of the peptides exhibited potentμ-receptor affinity and selectivity,among them,compound 7(Dmt-Pro-Tmp-Tmp-NH_2) exhibited potent affinity for bothμ-andδ-receptors (K_iμ= 0.47 nmol/L,K_iδ= 1.63 nmol/L). 相似文献
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Barrette J Bellwied R Braun-Munzinger P Cleland WE Cormier T Dadusc G David G Dee J Diebold GE Dietzsch O Duek E Fatyga M Fox D Greene SV Germani JV Hall JR Hemmick TK Herrmann N Hogue RW Hong B Jayananda K Kraus D Kumar BS Lacasse R Lissauer D Llope WJ Ludlam TW Majka R Makowiecki D Mark SK Mitchell JT Muthuswamy M O'Brien E Pruneau C Rotondo FS Sandweiss J da Silva NC Simon-Gillo J Slaughter J Sonnadara U Stachel J Takai H Takagui EM Throwe TG Waters L Winter C Wolf K Wolfe D Woody CL Xu N 《Physical review letters》1993,70(12):1763-1766
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Employing both multireference configuration interaction (MRCI) and density functional theory (DFT) methods, we have studied the interaction of O? with a tetrahedral Al? cluster in the total spin triplet state. For a parallel to the base approach of O? facing an apex of the pyramid, the O? adsorption is hindered by a barrier. Both the MRCI and the DFT calculations show that after a small barrier, there are two local energy minima: a shallow one just above the apex atom and another deeper one below the apex atom. The latter corresponds to dissociative O? adsorption. We discuss the implications of these findings for the understanding of O? adsorption on defect sites of Al surfaces. 相似文献
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Radiative decay from doubly to singly excited states of He via generalization of Laguerre-type orbitals: A non-orthogonal formalism
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By taking full account of the non-orthogonality of the orbitals
between the low-lying doubly excited states 1Po and the
singly excited states 1Se and 12De of He, the
corresponding radiative decay rates have been investigated
theoretically via analytic generalized Laguerre-type atomic orbitals
at a nearly numerical multi-configuration self-consistent field
accuracy in a general non-orthogonal configuration interaction
scheme. From these rates, we calculate the VUV photon emission and
metastable atom spectra, and both are found to be in good qualitative
agreement with recent excellent measurements. We obtain,
successfully, the enhancement of the VUV photon spectrum,
experimentally observed at the energy of (2s4p-4s2p)/(2p,3d)
1Po as compared with other nearby lying states. The
mechanism proposed by Odling-Smee et al is verified, implying
that taking appropriate account of the overlap existing between
orbitals of the low-lying doubly excited and singly excited states
(especially important for the compact orbitals) can reveal basic
physical dominant mechanism and is crucial in understanding these
spectra. 相似文献
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传统的利用变分原理求解Schrfidinger方程获得原子激发态波函数的方法是基于HUM理论(HylleraasUndheim and MacDonald theorem),在有限的N维Hilbert空间中,通过求解久期方程的高阶根获得激发态的近似波函数.在我们前期的工作中已指出,由于HUM方法的几个内禀缺陷限制,它将导致在相同的函数空间中,由传统变分法得到的激发态波函数的‘质量’远差于足够好的基态波函数.进一步地,为了避免基于HUM方法的变分缺陷,本文提出了新的变分函数,并证明其试探激发态波函数在其本征态处具有局域极小值,因而可以通过变分极小无限制的逼近该本征态.在此基础上,利用广义的Laguerre类型轨道(GLTO)在组态相互作用的框架下,分别编写了基于传统HUM理论和新变分函数的关于求解原子近似波函数的计算程序,并且利用该程序计算了氦原子(He)在1S(e),1P(o)态下相应的基态及激发态近似波函数及对应的能量值和径向平均值,并与已有文献中结果进行比较,计算结果显示了HUM理论的缺陷及新变分函数优越性,并就进一步提高激发态的精度指明了方向. 相似文献