中国物理B ›› 2012, Vol. 21 ›› Issue (7): 78202-078202.doi: 10.1088/1674-1056/21/7/078202

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

Theoretical study of structure and analytic potential energy function for the ground state of PO2 molecule

曾晖, 赵俊   

  1. School of Physical Science and Technology, Yangtze University, Jingzhou 434023, China
  • 收稿日期:2011-10-11 修回日期:2012-01-12 出版日期:2012-06-01 发布日期:2012-06-01
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant No. 11047176 ) and the Research Foundation of Education Bureau of Hubei Province, China (Grant Nos. Q20111305 and B20101303).

Theoretical study of structure and analytic potential energy function for the ground state of PO2 molecule

Zeng Hui(曾晖) and Zhao Jun(赵俊)   

  1. School of Physical Science and Technology, Yangtze University, Jingzhou 434023, China
  • Received:2011-10-11 Revised:2012-01-12 Online:2012-06-01 Published:2012-06-01
  • Contact: Zhao Jun E-mail:zhaojun@yangtzeu.edu.cn
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant No. 11047176 ) and the Research Foundation of Education Bureau of Hubei Province, China (Grant Nos. Q20111305 and B20101303).

摘要: In this paper, the energy, the equilibrium geometry, and the harmonic frequency of the ground electronic state of PO2 are computed using B3LYP, B3P86, CCSD(T), and QCISD(T) methods in conjunction with 6-311++G(3df, 3pd) and cc-pVTZ basis sets. A comparison between the computational results and the experimental values indicates that the B3P86/6-311++G(3df, 3pd) method can give better energy calculation results for the PO2 molecule. It is shown that the ground state of the PO2 molecule has C2v symmetry and its ground electronic state is X2A1. The equilibrium parameters of the structure are RP-O=0.1465 nm, d=19.218 eV. The bent vibrational frequency ν1=386 cm-1, the symmetric stretching frequency ν2=1095 cm-1, and the asymmetric stretching frequency ν3=1333 cm-1 are obtained. On the basis of atomic and molecular reaction statics, the reasonable dissociation limit for the ground state of the PO2 molecule is determined. Then the analytic potential energy function of the PO2 molecule is first derived by using the many-body expansion theory. The potential curves correctly reproduce the configurations and the dissociation energy for the PO2 molecule.

关键词: PO2, Murrell--Sorbie function, many-body expansion theory, potential energy curve

Abstract: In this paper, the energy, the equilibrium geometry, and the harmonic frequency of the ground electronic state of PO2 are computed using B3LYP, B3P86, CCSD(T), and QCISD(T) methods in conjunction with 6-311++G(3df, 3pd) and cc-pVTZ basis sets. A comparison between the computational results and the experimental values indicates that the B3P86/6-311++G(3df, 3pd) method can give better energy calculation results for the PO2 molecule. It is shown that the ground state of the PO2 molecule has C2v symmetry and its ground electronic state is X2A1. The equilibrium parameters of the structure are RP-O=0.1465 nm, d=19.218 eV. The bent vibrational frequency ν1=386 cm-1, the symmetric stretching frequency ν2=1095 cm-1, and the asymmetric stretching frequency ν3=1333 cm-1 are obtained. On the basis of atomic and molecular reaction statics, the reasonable dissociation limit for the ground state of the PO2 molecule is determined. Then the analytic potential energy function of the PO2 molecule is first derived by using the many-body expansion theory. The potential curves correctly reproduce the configurations and the dissociation energy for the PO2 molecule.

Key words: PO2, Murrell--Sorbie function, many-body expansion theory, potential energy curve

中图分类号:  (Chemical analysis and related physical methods of analysis)

  • 82.80.-d
31.10.+z (Theory of electronic structure, electronic transitions, and chemical binding) 33.15.Fm (Bond strengths, dissociation energies)