化学学报 ›› 2009, Vol. 67 ›› Issue (5): 397-402. 上一篇    下一篇

研究论文

[GeCN2]分子异构化势能面的理论研究

张文斌 石国升 丁益宏* 孙家钟

  

  1. (吉林大学理论化学研究所 理论化学计算国家重点实验室 长春 130023)

  • 投稿日期:2008-01-22 修回日期:2008-04-22 发布日期:2009-03-14
  • 通讯作者: 丁益宏

Theoretical Potential Energy Surface Investigation on the [GeCN2] Molecule

Zhang, Wenbin Shi, Guosheng Ding, Yihong* Sun, Jiazhong   

  1. (State Key Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry,
    Jilin University, Changchun 130023)
  • Received:2008-01-22 Revised:2008-04-22 Published:2009-03-14
  • Contact: Ding, Yihong

在CCSD(T)/6-311+G(2df)//B3LYP/6-311+G(d)水平下, 研究了四原子分子 [GeCN2]的各个异构体的几何结构、红外振动光谱、相对能量及异构化和解离稳定性, 构建了[GeCN2]势能面. 我们得到了7个[GeCN2]异构体, 包括5个直线型结构GeNCN (1), GeNNC (2), NGeCN (3), NGeNC (4), GeCNN (5)和2个环形结构Ge-cCNN (6)和Ge-cNCN (7). 其中异构体5, 6, 7是我们新找到的构型, 而且GeCNN (5)是整个势能面上稳定性仅次于GeNCN (1)的异构体. 几何和电子结构分析表明, GeCNN (5)具有共轭三键结构: Ge≡C—N≡N:. 由于具有良好的热力学和动力学稳定性, 异构体GeCNN (5)有望在实验中观测到. 我们建议利用过渡金属羰基化合物的络合作用可以进一步稳定GeCNN (5). 本研究为寻找新型含高周期元素的多重键化合物提供了理论线索.

关键词: Ge≡C—N≡N, 三重键, 势能面, 稳定性

At the CCSD(T)/6-311+G(2df)//B3LYP/6-311+G(d) level, the geometries, infrared vibrational spectrum, relative energies as well as the isomerization and dissociation stability of a tetra-atomic molecule [GeCN2] were studied. A detailed [GeCN2] potential energy surface was constructed, and seven [GeCN2] isomers were located, covering five linear forms GeNCN (1), GeNNC (2), NGeCN (3), NGeNC (4), GeCNN (5), and two cyclic forms Ge-cCNN (6) and Ge-cNCN (7). Amongst, the isomers 5, 6 and 7 are our newly-found species. In particular, the isomer GeCNN (5) is the second most-stable one on the overall [GeCN2] potential energy surface. The structural and electronic analysis indicates that the GeCNN (5) possesses a conjugate triply bonded structure |Ge≡C—N≡N|. Since the GeCNN (5) has good thermodynamic and kinetic stability, it was expected to be observable in laboratory. Finally, it was found that coordination by transition metal carbonyl complexes could further stabilize the GeCNN (5). The present study could provide useful theoretical clues for future search of potential multiply bonded molecules containing higher-row elements.

Key words: Ge≡C—N≡N, triple bond, potential energy surface, stability