摘 要采用了Dmol3软件中的密度泛函理论(Density Functional Theory, DFT)研究了WnMo(n=1-6)团簇，在几何全优化后得出了基态构型，并在基态构型的基础上计算了相关的物理化学性能，其主要结论如下：87099
1。 WnMo (n=1-6)团簇的基态结构，多重度均较低，其中WMo团簇为线性结构，W2Mo团簇为平面结构，当n≥3时，结构由二维变成三维。随着团簇原子数目的增长W-Mo的平均键长增加。
2。通过对WnMo (n=1-6)团簇的稳定性分析发现: WnMo (n=1-6)团簇的平均结合能，随着W原子数的增加团簇越来越稳定；二阶能量差分与平均结合能的变化趋势基本一致。
3。为了研究WnMo (n=1-6)团簇的化学活性，对它的能隙进行了分析，结果表明，当n=1、3、5时，WnMo团簇的能隙值较大，表明WMo、W3Mo、W5Mo团簇的化学活性较弱，而化学稳定性较强。
4。通过对磁性的研究发现，n=1、2、5的团簇磁矩较小团簇本身不显磁性；其中W3Mo和W4Mo团簇中所有原子周围电子均自旋向上团簇磁性较大。
5。红外光谱分析表明：团簇的振动频率范围大都分布在100-300cm-1处，峰值在0-5km。mol-1范围内；WMo、W3Mo和W4Mo团簇的振动强度较大。在频率为0-400cm-1范围内波峰较多的为W5Mo、W6Mo团簇，红外光谱峰值数目随着原子数目的增多呈上升趋势。
毕业论文关键词：WnMo团簇；基态结构；平均结合能；磁矩; 红外光谱;
Abstract We use Density Functional Theory (DFT) in the Dmol3 package to study the structures of WnMo(n=1-6) clusters 。Basing on them some relative physicochemical properties were calculated we find the lowest energy structure as the ground state structures and the results are as follows:
(1) In the of state structures of WnMo (n=1-6)clusters , multiple degrees were lower, of which WMo clusters is linear structure, W2Mo clusters is planar structure, when n≥3, the structure consists of a two-dimensional into three-dimensional。 The average atomic number of W-Mo key length grow when clusters increases。
(2) By analyzing WnMo (n=1-6)clusters stability, For WnMo (n=1-6)average binding energy are more stable with increasing of the W atoms 。The second order differential energy trends and average binding energy are basically the same。
(3)In order to study the chemical activity of clusters, we analyzed its energy gap ;the results showed that when n = 1,3,5, the energy gap of WnMo clusters are larger 。 Indicating that chemical activity of WMo, W3Mo, W5Mo clusters are weak, chemical stability are strong。
(4)Through the study of magnetic discovery, n=1,2,5 clusters have small magnetic moment ,the cluster itself is nonmagnetic。The electrons around all the atoms are spin up,the magnetism of clusters are larger。
(5)Infrared spectroscopy showed: clusters vibration frequency range mostly distributed in the 100-300cm-1。When the peak range in 0-5km。mol-1 ,the vibration intensity of WMo W3Mo and W4Mo Clusters are larger。 Within 0-400cm-1 W5Mo, W6Mo clusters have more peaks。 With the increase in the number of atoms IR peak’s number is rising。
Keywords: tungsten clusters; State structures; The average binding energy; Moments ;IR spectrum ;
目 录
第一章 绪论 1
1。1 团簇和团簇科学 1
1。1。1 团簇、混合/掺杂团簇 1
1。1。2 团簇的性质 1
1。1。3 团簇研究的意义和前景 2
1。2 钨基团簇研究进展 2
1。2。1 过渡金属团簇的研究 2 WnMo(n=1-6)小团簇的第一性原理研究:http://www.youerw.com/shuxue/lunwen_124610.html