Absorption Characteristics and Simulation of LLM-105 in the Terahertz Range
MENG Zeng-rui1, 2, SHANG Li-ping3, DU Yu2, 4*, DENG Hu1
1. School of Information Engineering, Southwest University of Science and Technology, Mianyang 621010, China 2. Institute of Chemical Materials, China Academy of Engineering Physics, Mianyang 621900, China 3. Laboratory for Extreme Conditions Matter Properties, Southwest University of Science and Technology, Mianyang 621010, China 4. Terahertz Research Center, China Academy of Engineering Physics, Mianyang 621900, China
Abstract：2,6-diamino-3,5-dinitropyrazine-1-oxide (LLM-105), a novel explosive with high energy and low sensibility. In order to study the molecular structure characteristics of the explosive, the absorption spectra of LLM-105 in the frequency range of 0.2 ～2.4 THz were detected by terahertz time-domain spectroscopy (THz-TDS). The results showed that a number of characteristic absorption peaks with different intensity located at 1.27，1.59，2.00，2.08，2.20，2.29 THz. The article also simulated the absorption spectra of LLM-105 molecular crystal within 0.2～2.5 THz region by using Materials Studio 6.0 software based on density functional theory (DFT), and the simulated results agreed well with the experimental data except for the peak at 2.29 THz, which verified theoretically the accuracy of the experimental data. In addition, the vibrational modes of the characteristic peaks in the experimental absorption spectra were analyzed and identified, the results showed that the forming of the characteristic absorption peaks and the molecular vibration were closely related, which further provided important laboratory and technology support for the study of the transformation of molecule structure of LLM-105. There was no simulated frequency agreed with the experimental absorption peak at 2.29 THz, which may be caused by the vibration of the crystal lattice or other reasons.
[1] LI Hai-bo, CHENG Bi-bo, LIU Shi-jun, et al(李海波，程碧波，刘世俊，等). Chinese Journal of Energetic Materials(含能材料)，2008, 16(6): 686. [2] WANG You-bing, GE Zhong-xue, WANG Bo-zhou, et al(王友兵，葛忠学，王伯周，等). Chinese Journal of Energetic Materials(含能材料)，2011, 19(5): 523. [3] WANG You-bing, DENG Ming-zhe, LIAN Peng, et al(王友兵，邓明哲，廉 鹏，等). Chinese Journal of Explosives & Propellants(火炸药学报)，2013, 36(1): 38. [4] XU Jing-zhou, ZHANG Xi-cheng(许景周，张希成). Terahertz Science Technology and Applications(太赫兹科学技术与应用). Beijing: Peking University Press(北京：北京大学出版社)，2007. [5] Fitch M J, Leahy-Hoppa M R, Ott E W, et al. Chemical Physics Letters, 2007, 443: 284. [6] Steven Pellizzeri, Sean p Delaney, Timothy M Korter, et al. Journal of Molecular Structure, 2013, 1050: 27. [7] WANG Gao, XU De-gang, YAO Jian-quan(王 高, 徐德刚, 姚建铨). Spectroscopy and Spectral Analysis(光谱学与光谱分析)，2013，33(4): 886. [8] WANG Gao, LI Qian, YAO Jian-quan, et al(王 高，李 茜，姚建铨，等). Initiators & Pyrotechnics(火工品)，2011，(4): 40. [9] Dorney T D, Baraniuk R G, Mittleman D M. Journal of the Optical Society of America A, 2001, 18: 1562. [10] Hooper J, Mitchell E, Konek C, et al. Chemical Physics Letters, 2009, 467(4): 309. [11] Daniel V Nickel, Sean P Delaney, Hongtao Bian, et al. The Journal of Physical Chemistry A, 2014, 118(13): 2442. [12] Steven Pellizzeri, Sean p Delaney, Timothy M Korter, et al. The Journal of Physical Chemistry A, 2014, 118(2): 417. [13] Huang L, Shabaev A, Lambrakos S G, et al. Vibrational Spectroscopy, 2013, 64: 62. [14] Ewelina M Witko，Timothy M Korter. The Journal of Physical Chemistry A, 2012, 116(25): 6879. [15] Allen F H, Kennard O. Chemical Design Automation News, 1993, 8(1): 1, 31.
