中国物理B ›› 2018, Vol. 27 ›› Issue (9): 93102-093102.doi: 10.1088/1674-1056/27/9/093102

• SPECIAL TOPIC—Recent advances in thermoelectric materials and devices • 上一篇    下一篇

Diffusion Monte Carlo calculations on LaB molecule

Nagat Elkahwagy, Atif Ismail, S M A Maize, K R Mahmoud   

  1. 1 Department of Physics, Faculty of Science, Kafrelsheikh University, Kafr El-Sheikh, Egypt;
    2 Department of Physics, Faculty of Applied Sciences, Umm Al Qura University, Makkah, Saudi Arabia;
    3 Department of Physics, Faculty of Science, Menoufia University, Shebin El-Kom, Egypt
  • 收稿日期:2018-04-04 修回日期:2018-06-14 出版日期:2018-09-05 发布日期:2018-09-05
  • 通讯作者: Nagat Elkahwagy E-mail:nagat_mhd@yahoo.com

Diffusion Monte Carlo calculations on LaB molecule

Nagat Elkahwagy1, Atif Ismail1,2, S M A Maize3, K R Mahmoud1   

  1. 1 Department of Physics, Faculty of Science, Kafrelsheikh University, Kafr El-Sheikh, Egypt;
    2 Department of Physics, Faculty of Applied Sciences, Umm Al Qura University, Makkah, Saudi Arabia;
    3 Department of Physics, Faculty of Science, Menoufia University, Shebin El-Kom, Egypt
  • Received:2018-04-04 Revised:2018-06-14 Online:2018-09-05 Published:2018-09-05
  • Contact: Nagat Elkahwagy E-mail:nagat_mhd@yahoo.com

摘要:

Potential energy curves for the lowest electronic states of LaB and LaB- have been calculated by ab initio calculations. The diffusion Monte Carlo method has been employed in combination with three different trial functions. Spectroscopic constants have also been numerically derived for the neutral molecule and compared with the only available theoretical work;[19] however, predictions are provided for the corresponding constants for the anionic species which have not been reported yet. Our calculations suggest the high spin quintet state of LaB as the ground state with the triplet state higher in energy irrespective of the type of the functional used. This suggestion is in good accordance with the previous theoretical results calculated at B3LYP/LANL2DZ level of theory, whereas it contradicts with the prediction based upon B3LYP/SDD calculations in the same study. Moreover, variations of the permanent dipole moments as a function of the internuclear separations for the two electronic states of the neutral molecule have been studied and analyzed.

关键词: potential energy curve, lanthanum boride, diffusion Monte Carlo, dipole moment

Abstract:

Potential energy curves for the lowest electronic states of LaB and LaB- have been calculated by ab initio calculations. The diffusion Monte Carlo method has been employed in combination with three different trial functions. Spectroscopic constants have also been numerically derived for the neutral molecule and compared with the only available theoretical work;[19] however, predictions are provided for the corresponding constants for the anionic species which have not been reported yet. Our calculations suggest the high spin quintet state of LaB as the ground state with the triplet state higher in energy irrespective of the type of the functional used. This suggestion is in good accordance with the previous theoretical results calculated at B3LYP/LANL2DZ level of theory, whereas it contradicts with the prediction based upon B3LYP/SDD calculations in the same study. Moreover, variations of the permanent dipole moments as a function of the internuclear separations for the two electronic states of the neutral molecule have been studied and analyzed.

Key words: potential energy curve, lanthanum boride, diffusion Monte Carlo, dipole moment

中图分类号:  (Electron electric dipole moment)

  • 31.30.jp
31.50.Bc (Potential energy surfaces for ground electronic states)