密度泛函理论研究叠氮二氢铟多聚体的结构与性质

Density Functional Theory Study on the Structures and Properties of(H_2InN_3)_(1～4) Clusters

在DFT-B3LYP/lanl2dz水平上计算研究了叠氮二氢铟多聚体(H2InN3)n(n=1～4)的结构和性质.(H2InN3)2～4多聚体的全优化几何构型均为环状构型,若单体连接方式为H2In-Nα-Nβ-Nγ,则多聚体通过一子体系叠氮基的α-N和另一子体系的In原子相连,即In-N-In结合方式.二聚体(H2InN3)2中含In2N2平面四元环结构.拥有船式和椅式两种构象的两个三聚体(H2InN3)3的结合能相近,均含In3N3六元环结构.具有In4N4八元环结构的四个四聚体的能量稍有差别.与单体相比,结构参数变化较大.同时报导了单体和多聚体在不同温度下的热力学性质,发现叠氮二氢铟体系是二聚体、三聚体和四聚体的平衡共存体.

DFT/B3LYP method with lan12dz basis set has been applied to the systems of （H2InN3）, （n=1 to 4）. The optimized （H2InN3）2-4 clusters are all cyclic structures, and （H2InN3）2-4 clusters are formed by In atoms bridged by the α-nitrogen of the azide groups （connectivity： H2In-Nα-Nβ-Nγ）, that is, （H2InN3）2--4 clusters contain In-N-In linkages. （H2InN3）2 is found to exhibit the planar In2N2 ring structure. The boat-like and chair-like trimers involving a six-membered In3N3 ring are found to exhibit two minima with very similar binding energies. The tetramers involving a eight-membered In4N4 ring have four structures that correspond to minima with slightly different binding energies. Compared to the monomer, the structural changes for the clusters are large. Thermodynamic properties reveal H2InN3 systems occur dimer-trimer-tetramer equilibriums.