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1.
黄元河  谢前  刘若庄 《化学学报》1993,51(9):865-868
用一维自洽场晶体轨道法探讨了过渡金属夹心高聚物[(C~4BH~5)M]~n(M=Cr,Mn,Fe,Co,Ni)的一维链结构和电子结构.计算表明,堆积单元(C~4BH~5)M中价电子数为奇数的高聚物结构会发生Peierls畸变,而价电子数为偶数的将取规则结构,由能带结构得到, [(C~4BH~5)Mn]~n的前线能带出现交叉,可能会发生进一步的结构畸变,但也有可能保持非满状态,成为异体.[(C~4BH~5)Ni]~n可能是不稳定的.其余三个高聚物为半导体或绝缘体,这系列高聚物电荷载流子通路主要依赖于金属d轨道重叠.  相似文献   
2.
本文报道了十四个内酯型(包括脂肪和芳香类)冠醚的EIMS行为,借助于精确质量测定、联动扫描、去焦技术以及同位素氘标记,对它们的碎裂方式作了详尽的总结和讨论,对于其中十个化合物的FD谱图特点也作了相应的归纳。  相似文献   
3.
对以正十六烷、油酸钾、正己醇和水所组成的微乳液进行研究,对其流变性和机理作了探讨.微乳液粘度和水油比变化的关系可用相转化来说明.层形结构区显示出有高粘度特征,并具有明显的负触变性现象.对此进行了讨论,并研究了pH值和盐类的影响.  相似文献   
4.
闵新民  江元生 《化学学报》1988,46(9):868-874
多重散射Xα方法讨论了氟苯、苯胺、硝基苯和苯腈的电离能、π轨道的电荷分布、π轨道的系数及等值图形. 表明多重散射Xα方法的波函数和电荷分布在描述取代苯活化位置方面存在某种局限性, 讨论了改善的可能途径.  相似文献   
5.
In 1975, Ashtekar and Magnon showed that anenergy condition selects a unique quantization procedurefor hypersurface orthogonal observers in general, curvedspacetimes. We generalize this result in two important ways, by eliminating the need toassume a particular form for the (quantum) Hamiltonian,and by considering the surprisingly nontrivial extensionto non-minimal coupling, for which the classical Hamiltonian differs from the classical energycalculated from the stress-energy tensor.  相似文献   
6.
It is shown that uncharged test particles, released from rest at infinity in the Kerr-Newman field, stop and rebound when the radial coordinate r takes the value r0 = Q2/(2M). This expression corresponds to the position of a stationary source of the Kerr-Newman field found by the author. It represents the surface of a massive oblate ellipsoid of revolution undergoing rigid rotation. Besides, the magnitude of r0 guarantees that no violation of causality occurs throughout spacetime. Although the test particles' angular momenta are always zero, they acquire a rotational motion as a consequence of the dragging of inertial frames.  相似文献   
7.
8.
In this paper, nineteen FD mass spectra of cyclic nucletides are repoted. The results indicated that only (M+ + H) peak presents in the spectra of cy-AMP, cy-CMP and cy-UMP. The derivatives of cy-AMP (except 7) have M+, (M+ + H) peaks, and the main fragments corresponding to (B + 1), (T + 1) peaks as shown in Fig. 1 in the Chinese Text. The adenosine 3', 5'-cyclic phosphite and its derivatives with P(III) are somewhat different as compared with P(Ve. In some cases neither M+ nor (M+ + H) is present in their spectra, but there are some characteristic peaks. Their fragmentation process has been shown in Fig. 2 in the Chinese Text.  相似文献   
9.
According to Poincaré, only the epistemological sum of geometry and physics is measurable. Of course, there are requirements of measurement to be imposed on geometry because otherwise the theory resting on this geometry cannot be physically interpreted. In particular, the Weyl-Cartan space problem must be solved, i.e., it must be guaranteed that the comparison of distances is compatible with the Levi-Civita transport. In the present paper, we discuss these requirements of measurement and show that in the (purely affine) Einstein-Schrödinger unified field theory the solution of the Weyl-Cartan space problem simultaneously determines the matter via Einstein's equations. Here the affine field i kl represents Poincaré's sum, and the solution of the space problem means its splitting in a metrical space and in matter fields, where the latter are given by the torsion tensor i [kl].  相似文献   
10.
胞嘧啶稀土配合物的振动光谱和结构研究   总被引:1,自引:0,他引:1  
在无水体系中首次合成三种胞嘧啶稀土配合物Ln(Cyt)2(NO3)3(Ln=La, Ce, Gd)。振动光谱的实验频谱分析以及SAS值和量子化学计算结果, 表明该系列配合物以两个胞嘧啶分子在N(3)和C(2)=O(1)位同稀土配位, 两个硝酸根双齿配位, 形成八配位稀土配合物, 属C2h分子点群。  相似文献   
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