中国物理B ›› 2015, Vol. 24 ›› Issue (8): 88103-088103.doi: 10.1088/1674-1056/24/8/088103

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

Path integral Monte Carlo study of (H2)n@C70 (n=1,2,3)

郝妍a, 张红b, 程新路a   

  1. a Institution of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, China;
    b College of Physical Science and Technology, Sichuan University, Chengdu 610065, China
  • 收稿日期:2015-01-17 修回日期:2015-03-12 出版日期:2015-08-05 发布日期:2015-08-05
  • 基金资助:

    Project supported by the National Natural Science Foundation of China (Grant Nos. 11474207 and 11374217).

Path integral Monte Carlo study of (H2)n@C70 (n=1,2,3)

Hao Yan (郝妍)a, Zhang Hong (张红)b, Cheng Xin-Lu (程新路)a   

  1. a Institution of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, China;
    b College of Physical Science and Technology, Sichuan University, Chengdu 610065, China
  • Received:2015-01-17 Revised:2015-03-12 Online:2015-08-05 Published:2015-08-05
  • Contact: Zhang Hong E-mail:hongzhang@scu.edu.cn
  • Supported by:

    Project supported by the National Natural Science Foundation of China (Grant Nos. 11474207 and 11374217).

摘要:

The path integral Monte Carlo (PIMC) method is employed to study the thermal properties of C70 with one, two, and three H2 molecules confined in the cage, respectively. The interaction energies and vibrationally averaged spatial distributions under different temperatures are calculated to evaluate the stabilities of (H2)n@C70 (n=1, 2, 3). The results show that (H2)2@C70 is more stable than H2@C70. The interaction energy slowly changes in a large temperature range, so temperature has little effect on the stability of the system. For H2@C70 and (H2)2@C70, the interaction energies keep negative; however, when three H2 molecules are in the cage, the interaction energy rapidly increases to a positive value. This implies that at most two H2 molecules can be trapped by C70. With an increase of temperature, the peak of the spatial distribution gradually shifts away from the center of the cage, but the maximum distance from the center of H2 molecule to the cage center is much smaller than the average radius of C70.

关键词: endohedral fullerene complexes, path integral Monte Carlo method, interaction energy, vibrationally averaged spatial distribution

Abstract:

The path integral Monte Carlo (PIMC) method is employed to study the thermal properties of C70 with one, two, and three H2 molecules confined in the cage, respectively. The interaction energies and vibrationally averaged spatial distributions under different temperatures are calculated to evaluate the stabilities of (H2)n@C70 (n=1, 2, 3). The results show that (H2)2@C70 is more stable than H2@C70. The interaction energy slowly changes in a large temperature range, so temperature has little effect on the stability of the system. For H2@C70 and (H2)2@C70, the interaction energies keep negative; however, when three H2 molecules are in the cage, the interaction energy rapidly increases to a positive value. This implies that at most two H2 molecules can be trapped by C70. With an increase of temperature, the peak of the spatial distribution gradually shifts away from the center of the cage, but the maximum distance from the center of H2 molecule to the cage center is much smaller than the average radius of C70.

Key words: endohedral fullerene complexes, path integral Monte Carlo method, interaction energy, vibrationally averaged spatial distribution

中图分类号:  (Fullerenes and related materials)

  • 81.05.ub
05.10.Ln (Monte Carlo methods) 65.80.-g (Thermal properties of small particles, nanocrystals, nanotubes, and other related systems) 68.60.Dv (Thermal stability; thermal effects)