中国物理B ›› 2015, Vol. 24 ›› Issue (6): 68201-068201.doi: 10.1088/1674-1056/24/6/068201

• INTERDISCIPLINARY PHYSICS AND RELATED AREAS OF SCIENCE AND TECHNOLOGY • 上一篇    下一篇

Theoretical investigation on isomer formation probability and free energy of small C clusters

林正喆   

  1. School of Physics and Optoelectronic Engineering, Xidian University, Xi'an 710071, China
  • 收稿日期:2014-10-03 修回日期:2015-01-15 出版日期:2015-06-05 发布日期:2015-06-05
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant No. 11304239) and the Fundamental Research Funds for the Central Universities.

Theoretical investigation on isomer formation probability and free energy of small C clusters

Lin Zheng-Zhe (林正喆)   

  1. School of Physics and Optoelectronic Engineering, Xidian University, Xi'an 710071, China
  • Received:2014-10-03 Revised:2015-01-15 Online:2015-06-05 Published:2015-06-05
  • Contact: Lin Zheng-Zhe E-mail:linzhengzhe@hotmail.com
  • About author:82.30.Nr; 31.15.xv
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant No. 11304239) and the Fundamental Research Funds for the Central Universities.

摘要: Molecular dynamics simulations and free energy calculations are employed to investigate the evolution, formation probability, detailed balance, and isomerization rate of small C cluster isomer at 2500 K. For C10, the isomer formation probability predicted by free energy is in good agreement with molecular dynamics simulation. However, for C20, C30, and C36, the formation probabilities predicted by free energy are not in agreement with molecular dynamics simulations. Although the cluster systems are in equilibrium, detailed balance is not reached. Such results may be attributed to high transformation barriers between cage, bowl, and sheet isomers. In summary, for mesoscopic nanosystems the free energy criterion, which commonly holds for macroscopic systems in dynamic equilibrium, may not provide a good prediction for isomer formation probability. New theoretical criterion should be further investigated for predicting the isomer formation probability of a mesoscopic nanosystem.

关键词: isomer formation probability, isomer free energy

Abstract: Molecular dynamics simulations and free energy calculations are employed to investigate the evolution, formation probability, detailed balance, and isomerization rate of small C cluster isomer at 2500 K. For C10, the isomer formation probability predicted by free energy is in good agreement with molecular dynamics simulation. However, for C20, C30, and C36, the formation probabilities predicted by free energy are not in agreement with molecular dynamics simulations. Although the cluster systems are in equilibrium, detailed balance is not reached. Such results may be attributed to high transformation barriers between cage, bowl, and sheet isomers. In summary, for mesoscopic nanosystems the free energy criterion, which commonly holds for macroscopic systems in dynamic equilibrium, may not provide a good prediction for isomer formation probability. New theoretical criterion should be further investigated for predicting the isomer formation probability of a mesoscopic nanosystem.

Key words: isomer formation probability, isomer free energy

中图分类号:  (Association, addition, insertion, cluster formation)

  • 82.30.Nr
31.15.xv (Molecular dynamics and other numerical methods)