吸附原子

In addition, some modifications on several computational methods are also presented. Using LMTO method the electronic structure of several systems are studied, and some results are obtained. They are: The ideal Nb (100) surface has three surface states, the multi-layer relaxed surface has two surface states. The surface energy of the ideal surface is higher than that of the relaxed surface, that means that the multi-layer relaxed surface is more stable than the former one, which supports the LEED results. The mono-layer relaxed Ag (111) surface is the most stable one among several" stable surface models"presented by several researchers. The surface energy of Ag (111) surface is higher than that of surface Ag (001), which supports some experimental results such as different reaction rate at different surface orientations for the same material. The surafce states of Si (111) surface not only locate near the Fermi level, but also in the valence band, which agrees well with Cohen's conclusion. Si (111)-H is an effective model for analysing the surface states and H adsorbed on the back surface is a good method for improving the convincingness of the results obtained on thinner slab models. The surface stability depends on three different kinds of MoSi〓(001) surfaces, the surface with mono-layer Si is the most stable one, and the surface with Mo at the first layer is the most unstable one among them. These are consistant with the Kemoda's experimental results. The valence bands of clean or K adsorbed CdTe (111) surface agrees well with the synchrotron radiation studies. The surface of CdTe (111) consists of four kinds of surface models which show different surface electronic structures and different surface structure stabilities. The conclusion agrees well with Wu's experimental work. The different absorbed alkali metals on the CdTe (111) surface give different adsorption characteristics which have relations not only with the valence electrons, but also with the core ones of the alkali metals. The electonic structures of Si-C alloys are different from that of Si-Ge alloys, and the energy band gaps of Si-C alloys do not increase linearly with Carbon concentration, our conclusion supports Alexander's results, but conflicts with Soref's one.

现分述如下： LMTO方法及其应用方面：1）通过对Nb（100）表面电子态分析发现清洁理想表面有三个表面态，多层弛豫表面有两个表面态；表面能大小说明多层弛豫表面更稳定，支持了LEED结果。2）通过对采用不同方法获得的几种不同Ag（111）表面稳定结构的表面能计算分析，给出了单层弛豫表面为Ag（111）表面的最稳定结构；从Ag（111）单层弛豫表面和Ag（001）表面的表面能比较，发现了Ag（001）表面表面能要比Ag（111）小的，表明了同种物质不同表面取向将表现出不同物理、化学性质，这是与实验中得出的结论是吻合的，3）通过对Si（111）表面态分析，不仅发现了Si（111）表面不仅具有居于费米能级附近的悬挂键所对应的表面态，而且还有很多表面态位于价带能量范围内，与Cohen等结果一致，H饱和slab模型背表面相当于增加了slab层的厚度，是一有效的变相增加slab层厚的方法，弛豫表面较清洁理想表面价带谱们低能端的少许移动，预示着总能降低，说明弛豫表面较清洁理想表面稳定。4）MoSi〓具有三种表面，从费米能级上态密度值大小得到单层Si表面最稳定，Mo原子为表层原子的表面最不稳定，双层Si原子表面居中的结论，这与Kemoda等人实验结果是一致的。5）通过对CdTe（111）表面表面电子态、表面结构稳定性及表面H、碱金属吸附的电子结构系列研究，不仅得出了CdTe（111）清洁及碱金属K吸附价带谱与同步辐射光电子谱相吻合的结果，而且发现了CdTe（111）表面具有四类不同原子近邻特征，表现出四类不同的表面结构及电子结构特征：不同表面态分布、不同的表面结构稳定性（表层原子与次层原子成三键有一悬挂键的表面要比表层原子与次层原子成一键有三悬挂键稳定（与Wu等人实验结果一致））、不同的H吸附特性。

We have observed gaseous diatomic molecule on the semiconductor surface with the chemical-physics dynamic mechanism of the chemical adsorption on the dangling bond. We explored on the phenomena in how gas molecules dissolve, how the atoms move, and on how they replace the bondings during the chemical adsorption process on the surface.

本论文主要在研究气态双原子分子化学吸附於半导体表面悬键上的化学物里动力学机制，并探讨气体分子在表面化学吸附过程中的分子裂解、原子移动、取代键结等现象。

Each In atom is bonded with one Si atoms and two neighboring In atoms; b The adsorption energy of single In atom on the FHUC of the Si(111)-7x7 is 0.2eV higher than that on the UHUC. As a result, In atoms prefer to enucleate at the UHUC and develop into ordered dots array accordingly.

第一原理计算表明， a六个 In 原子在 Si(111)-7x7表面形成一种扭曲的六边形结构，每个 In 原子与一个衬底 Si 原子及两个相邻的 In 原子形成共价键，这些共价键具有类 sp2构型； b单个 In 原子吸附在 Si(111)-7x7单胞的 FHUC 时的吸附能较吸附在没有层错的一半的吸附能低0.2eV/原子，故而 In 团簇优先在 FHUC 成核生长并进而形成有序的点阵结构。

The calculated results show that H atom preoccupies the twofold bridge site of the subsurface on the intact W(100) surface at low coverage, and obtains the perpendicular vibration frequency of 156 meV. The H-atom adsorption on bridge site, top site and fivefold hollow site (the top site on the second W layer) were observed at high coverage.

计算结果表明，低覆盖度下， H原子优先吸附在W(100)面的内层吸附位二层桥位B'，获得156 meV的垂直振动频率，随着覆盖度的增加， H原子稳定吸附在表层的五重洞位、桥位及顶位。

Foreign atoms were placed over the sheet at several symmetrical positions, namely, over a carbon atom, over a C-C bond, over the center of a pentagonal, hexagonal, and heptagonal ring. The following conclusions have been drawn: The cohesive energy of adsorbate and perfect sheet at all three adsorption sites is always lower than that on a sheet with a Stone-Wales defect embedded at all five sites.

得到的主要结论如下：所有外来原子在含有Stone-Wales缺陷的石墨烯片上不同位置上吸附的结合能都大于在其在完整石墨烯片上不同位置上的结合能，因此在碳管中引入Stone-Wales缺陷能够提高原子在碳管上的吸附能力，同时提供了很多稳定的吸附位置。

The analyses of electronic structures shows that the catalytic reactivities for H2 adsorption of the different surfaces are dependent on the numbers of s orbital bonding electrons around Fermi level for the uppermost layer metal atoms which interact directly with H2. It is easy to form vacancy for hydrogen atoms next to iron atom, which indicates that hydrogen atom cannot be escaped, but it is difficult to from vacancy for hydrogen atoms next to magnesium atom, which indicates that hydrogen atom can be escaped. Hence it is thought that the change of dehydrogenating properties of MgH2 with or without a little iron addition attributes to the weakened bonding between magnesium and hydrogen.

分析电子结构发现：空位缺陷有助H2吸附于Mg表面，与Mg(0001)表面最上层与H2直接产生吸附作用的金属原子在费米能级附近s轨道的成键电子数密切相关；在Fe合金化MgH2体系中，与合金化元素Fe近邻的H原子形成空位的难度增加，H原子较难释放；与Mg近邻的H原子形成空位的难度减少，H原子容易释放；Fe合金化导致Mg-H之间存在较弱的成键作用，因此，MgH2体系的解氢性能得到提高。

However, atoms on the surface of the adsorbent are not wholly surrounded by other adsorbent atoms and therefore can attract adsorbates.

然而，表面原子的吸附剂也并非完全包围，所以可以等吸附剂原子吸附物吸引。

Using density functional theory, the adsorption of cyanide on the different sites of Cu(100) surface was studied with end-on and side-on geometries.

采用密度泛函方法，以原子簇Cu14 为模拟表面，对CN自由基分子在垂直和平行Cu( 10 0 )表面不同位置的吸附情况进行了研究，结果表明：通过原子C垂直吸附在表面的顶位是其最佳吸附方式，吸附后CN键振动频率发生蓝移；而其它吸附方式中CN键振动频率均发生红移。

We have come to the following conclusions:(1) the existence of the monoatomic layer is conditional, it depends upon the temperature, surface structure and purity of the substrate as well as upon the vacuum environment;(2) the appearance, and sometimes disappearance, of the emission peaks is a problem for further study, and it can not be explained simply by the monoatomic layer...

关于时而能、时而又不能观察到的电子发射峰值，是一个有待于进一步明确的现象，不能简单地用单原子层和偶极子理论来解释；3。吸附了外界原子或分子使电子发射增加的事实，并不是由于偶极矩降低了基底的逸出功，发射的电子来源于被吸附物质的价电子；4。实验证明&L&阴极是Ba-O-W系统，它既不是单原子层，也不是单分子层，也不适用偶极子理论。

The results showed that C 2H 6 can be adsorbed on the surface terminal oxygen of Lewis base site P=O bonds through H atom in -CH 3 to form a molecular adsorption state, and the adsorption intensity of C 2H 6 increases with the rising of adsorption temperature.

结果表明，乙烷能够以 CH3 中的H原子吸附于催化剂表面P =O键的端氧上形成分子吸附态，并且随着吸附温度的升高，对乙烷的吸附强度逐渐增大；乙烯则主要是以C =C双键吸附在催化剂的Lewis酸位Fe3 +上。

But we don't care about Battlegrounds.

但我们并不在乎沙场中的显露。

Ah! don't mention it, the butcher's shop is a horror.

啊！不用提了。提到肉，真是糟透了。