原子密度

Unfortunately, it has been shownthat these methods are not suitable to study about chemical bonds due to not involvingchemical bonds. In order to consider chemical bonds obviously, we have proposed an atom-bondelectronegativity equalization model on the basis of density-functionaltheory and electronegativity equalization principle. The main contents of our atom-bond electronegativity equalization model contain:(1)Considering the fact that there are varies of chemical bonds in molecules andpartitioning the molecular electron density as summations of atomic electron densitiesand chemical bond's electron densities, we obtained the basic equations of atom-bondelectronegativity equalization model: the expression of the total energy 〓, theexpression of the atom electronegativity 〓 and the expression of the bondelectronegativity 〓.

为了明确地考虑和处理分子中存在的化学键，以便能够更好地描述体系中的电荷分布进而准确地描述分子体系中的有关物理化学性质，尤其是与化学键有关的物理化学性质，我们在密度泛函理论和电负性均衡原理基础上提出了原子-键电负性均衡模型，原子-键电负性均衡模型的主要内容是：(1)考虑到分子体系中存在各种化学键这个事实，将分子空间看成是由原子区和化学键区组成的，将分子的单电子密度表达成为分子中各组成原子的单电子密度和各化学键的单电子密度的加和，从而得到了原子-键电负性均衡模型的基本方程：分子体系总能量〓和分子中原子电负性〓和化学键电负性〓表达式。

It was the large excess entropy of interface phase with a lower atomic density and high degree of disorder that stabilizes the formed nano-structure.

正是低原子密度且高度无序界面的过剩的熵稳定了所形成的纳米晶结构。

If the atomic density is small10~(13atoms/cm~3 or less such that local field effects are unimportant.

如果原子密度很小10~(13atoms/cm~3或更小，局域场效应可以忽略不计。

According to the principle of continuity of wave function, when different elements react with each other to form compound, the electronic densities of atoms at interface must be equal. Each atom should change the atomic radius to shift their electrical density, then this made huge micro-stress in atoms.

在单质元素原子形成化合物时，由于要满足量子力学的波函数连续原理，要求原子界面上的电子密度相等，各原子在化合时必须通过改变原子半径以达到相同的原子边界电子密度，从而在原子中产生了很大的微观内应力。

In this thesis, a semi-classical model of the force on an atom is used to describe the motion of a two-level atom interacting with a standing wave laser field. The velocity dependent force and momentum diffusion are derived through optical Bloch equations by using the matrix form of the continued fraction technique. By investigating the dynamic properties of atoms in laser field, we can control and manipulate the mechanical motion of an atom.

本文利用半经典理论，从二能级原子在激光驻波场中所满足的运动方程出发，推导出密度矩阵元所满足的递推关系，利用矩阵连分数方法求解出密度矩阵元，从而求出依赖于原子运动速度的光压力与动量扩散系数，通过讨论原子在激光场中的动力学行为，为原子在激光场中被囚禁、形成原子列阵以及可控制的量子态，从而为量子信息处理提供理论基础。

If only the interatomic force are considered, atomic stress amounts to the potential density in the resultant force field generated by the neighboring atoms, and atomic elastic constants equals to the potential density increment in the same resultant force field.

如果只考虑原子间作用力的影响，原子应力等于该原子在周围邻域原子合成张量力场中的势能密度，原子弹性常数等于发生单位应变时原子在邻域原子合成力场中势能密度的增量。

This showed that the electron density of a quinoid ring increased. The peaks of the quaternary carbon atoms of the benzene rings, which were adjacent to the quinoid ring, also shifted to higher field. But the peaks of other C atoms shifted to lower field.

NMR结果表明苯胺低聚体掺杂后主链上的电荷重新分布，环上的H原子上的电子被C原子吸引，电荷密度降低，在〓 NMR中谱峰向低场移动。C原子的谱峰也相应发生变化，醌环上电荷密度增加，全部C原子的峰向高场移动，与醌环相邻苯环受其影响季碳峰移向高场，非季碳峰移向低场。

In the 2A1 distorted trigonal bipyramid structure ,the single non equivalent Ga atom has the population of 4s 4p ,while the two equivalent Ga atoms have the population of 4s 4p .this compares with a Ga population of 4s 4p in the undistorted D3h structure ,hence the jahn-teller distortion causes depletion of the charge density on the 4s orbital of the non-equivalent Ga atom, and enhancement of charge density on the 4s orbital for the two equivalent atoms .an opposite trend is observed for the 4p orbitals of these Ga atoms .the P population for the two equivalent atoms is 3s 3p .the populations of the other 2B1 state with the edge-capped tetrahedral structure are similar with the exception that all three Ga atoms have similar but not identical populations .

在2A1被变形的三角bipyramid结构，唯一非等效Ga原子有4s 4p的人口，而二个等效Ga原子在未变形的D3h结构有4s 4p 。this的人口和4s相比4p的Ga人口，因此jahn出纳畸变在non-equivalent Ga原子的4s轨道导致电荷密度的取尽，并且电荷密度的改进在4s轨道为二个等效原子。an在趋向对面对这些Ga原子4p轨道被观察。the人口为二个等效原子是另一个2B1状态3s 3p 。the人口与边缘加盖的四面体结构是相似的P 除之外全部三个Ga原子有相似，但不相同人口。

The electron location function shows the electronic density changes at both the atomic vacancies and antisites. There is an obvious absence of electronic areas where the vacancy of Ga has the dangling bonds of N, which are favourable for the sdsorption of metal atoms. In contrast, at the vacancy of N, there is more electron distribution(ELF:0.16-0.45), forming lone electron pairs which are profitably available to combine electronegative atoms.

电子局域函数显示了表面空位和替位处的电子密度变化，表面Ga原子空缺处有非常明显的缺电子区域，悬挂键临近N的电子密度增大，有利于对金属原子的吸附；N原子空位处的ELF值为0.16-0.45，有利于同电负性较大的原子结合。

The results show that for SiO〓 and GeO〓 glasses, the Rayleigh scatterings arise mainly from the disorders of the densities of atoms, consistent with the assumption of the fictive temperature approximation which is the usual method used in the existing optical fiber theory to calculate Rayleigh scatterings in glasses.

计算结果表明：对SiO〓和GeO〓玻璃，现有光纤理论的瑞利散射处理方法——虚温度近似所作关于玻璃中瑞利散射主要来自玻璃的原子密度无序的假设能很好成立。

Since historical times,England ,where the early inhabitants were Celts, has been conquered three times .

从有历史以来，英国，在此地早期居住的是凯尔特人，已经被征服了三次。

Bluetooth OBEX File Transfer Enables the sending and receiving of files on your phone via Bluetooth.

蓝牙OBEX文件移动允许经过蓝牙传送和接受文件。。。。