理论研究不对称团簇(HFBN3)n (n=1-6)的结构和稳定性

Theoretical investigation of structures and stabilities for asymmetric clusters (HFBN3)n (n=1-6)

摘要:

采用密度泛函理论方法研究不对称团簇(HFBN3)n (n=1-6)的结构和性质。对于n≥2的团簇，B–Nα键易形成，而B–B和Nα–Nα键不存在。讨论了几何参数随团簇尺寸n的变化规律。通过分析团簇平均结合能和二阶差分值，探讨其相对稳定性，发现团簇(HFBN3)3比其它团簇更稳定。计算IR谱有四个特征区。研究了团簇的热力学性质随温度T以及团簇尺寸n的变化趋势。室温下，由焓变可知单体1形成多聚体（2、3、4、5、6）在热力学上有利。

Abstract:

Density functional theory has been applied to investigate the structures and properties of asymmetric clusters (HFBN3)n (n=1-6). When n≥2, B–Nα bonds form easily, and B–B and Nα–Nα bonds are not found in the clusters. The geometric parameters of clusters along with cluster size n are discussed. The relative stabilities of asymmetric clusters (HFBN3)n (n=1-6) are analyzed based on the averaged binding energy and second-order difference of energy. It is found that (HFBN3)3 clusters are more stable than other clusters. The calculated IR spectra have four main characteristic regions. Trends in thermodynamic properties with temperature T and cluster size n are discussed, respectively. Monomer 1 forms clusters (2, 3, 4, 5 and 6) thermodynamically favorable by the enthalpies at 298.2 K.