Acta Chim. Sinica ›› 2016, Vol. 74 ›› Issue (12): 1009-1017.DOI: 10.6023/A16090505 Previous Articles    

Special Issue: 聚集诱导发光

Article

二核铪氧簇Hf2On-/0(n=1~6)的电子性质与结构演化的理论研究

陈仕芳a, 陈文杰b, 王彬a, 章晓斌a, 黄昕a,c, 章永凡a,c   

  1. a 福州大学化学学院 福州 350116;
    b 泉州师范学院化工与材料学院 泉州 362000;
    c 福建省理论与计算化学重点实验室 厦门 361005
  • 投稿日期:2016-09-21 发布日期:2016-12-05
  • 通讯作者: 章永凡 E-mail:zhangyf@fzu.edu.cn
  • 基金资助:

    项目受国家自然科学基金(Nos.21371034,21301030,21373048和21603117)资助.

Theoretical Study on Electronic Properties and Structural Evolution in Hf2On-/0 (n=1~6) Clusters

Chen Shifanga, Chen Wenjieb, Wang Bina, Zhang Xiaobina, Huang Xina,c, Zhang Yongfana,c   

  1. a College of Chemistry, Fuzhou University, Fuzhou 350116;
    b College of Chemical Engineering and Material, Quanzhou Normal University, Quanzhou 362000;
    c Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, Xiamen 361005
  • Received:2016-09-21 Published:2016-12-05
  • Supported by:

    Project supported by the National Natural Science Foundation of China (Nos. 21371034, 21301030, 21373048 and 21603117).

Extensive density functional theoretical (DFT) and ab initio[CCSD (T)]calculations were combined to investigate the geometric and electronic structure of a series of dinuclear hafnium oxide clusters,Hf2On-/0(n=1~6).DFT calculations were performed to search for the lowest energy structures for both the anionic clusters and the neutral counterparts.The search for the global minima was performed using analytical gradients with the Stuttgart relativistic small core potential and the valence basis sets augmented with two f-type and one g-type polarization functions for Hf and the aug-cc-pVTZ basis set for oxygen.The relative energies of the low-lying structures (within ca.0.35 eV) were further evaluated via single-point calculations at the coupled cluster[CCSD (T)]level with the Hf/Stuttgart+2f1g/O/aug-cc-pVTZ basis sets at the B3LYP geometries.Generalized Koopmans' theorem (GKT) was applied to predict VDEs and simulate the anion photoelectron spectra (PES).The trends of structural evolution and the behavior of sequential oxidation of the Hf2On-(n=1~6) clusters were observed.For the anionic species,starting from the C2v triangular structure Hf2O-,the next O atom in the Hf2O2- cluster was again bridge-bonded,forming a rhombus structure.The third O atom occupied the terminal site.The fourth O atom favored the bridging site and the fifth O atom occupied the terminal site.In Hf2O6-,the additional O atom was bonded to a terminal site.Molecular orbital analyses were performed to elucidate the chemical bonding and the structural evolution in Hf2On-(n=1~4) clusters.Spin density analyses revealed oxygen radical,diradical and superoxide characters in the oxygen-rich clusters,except for the singlet Hf2O5 cluster.We showed that Hf2O3 contains a localized Hf2+ site,which can readily react with O2 to form the Hf2O5 cluster.The Hf2O6- and Hf2O6 clusters,which can be viewed to be formed by the interaction of Hf2O4-/0 and O2,may be utilized as molecular models to understand dioxygen activation on Hf2O4- and Hf2O4 clusters.

Key words: hafnium oxide cluster, DFT, CCSD (T), radical, simulated PES