Programme

O.11 -- Oral, VCTP-44

Date: Tuesday, 30 July 2019

Time: 11:40 - 12:00

Extracting molecular structure from the laser-induced electron diffraction spectra

Ngoc-Loan Phan(1), Hien T. Nguyen (2,3), Dinh-Duy T. Vu (4)

(1) Ho Chi Minh City University of Education, Ho Chi Minh City, Vietnam (2) Tay Nguyen University, Dak Lak, Vietnam (3) VNUHCM-University of Science, Ho Chi Minh City, Vietnam (4) University of Maryland, Maryland, USA

Laser-induced electron diffraction (LIED) has been found as a promising tool for molecular imaging with high spatiotemporal resolution [1, 2]. First, based on the quantitative rescattering theory [3] the laser-free elastic differential cross section (DCS) can be extracted from the LIED spectra. Then, by comparing with the theoretical DCS calculated by the independent-atoms model (IAM) of molecules, the molecular structures can be retrieved. This approach was applicable only for the mid-infrared laser, which induces electron-molecular collision with high energy [1, 2]. Therefore, we have recently upgraded the multiple-scattering model (MS) to expand the range of electron-ion collision to low energy induced by the near-infrared laser [4]. These IAM and MS models were useful in the reconstruction of the molecular information for not only diatomic but also polyatomic molecules but not including the vibration effect [1, 2, 4]. Many studies have shown the necessity of including the molecular vibration and anharmonicity in the DCS calculation of the conventional gas-phase electron diffraction [5, 6]. This inclusion leads to the right corrections of structural retrieval parameters of the molecules [5], or the shrinkage effect [6]. Therefore, the vibration and anharmonicity may affect the quality of extracting molecular structure from the electron-ion collision obtained from LIED spectra. In this report, we discuss the influence of molecular vibration on the electron-ion DCS and, consequently, on the extracted molecular structure from LIED spectra. [1] C. I. Blaga, J. Xu, A. D. DiChiara, E. Sistrunk, K. Zhang, P. Agostini, T. A. Miller, L. F. DiMauro, and C. D. Lin, Nature 483, 194 (2012). [2] B. Wolter, M. G. Pullen, A.-T. Le, M. Baudisch, K. Doblhoff-Dier, A. Senftleben, M. Hemmer, C. D. Schröter, J. Ullrich, T. Pfeifer, R. Moshammer, S. Gräfe, O. Vendrell, C. D. Lin, and J. Biegert, Science 354, 308 (2016). [3] Z. Chen, A. T. Le, T. Morishita, and C. D. Lin, Phys. Rev. A 79, 033409 (2009). [4] D. D. T. Vu, N. L. T. Phan, V. H. Hoang, and V. H. Le, J. Phys. B 50, 245101 (2017). [5] L. S. Bartell, J. Chem. Phys. 1219, 1219 (2006). [6] M. Tanimoto, K. Kuchitsu, and Y. Morino, Bull. Chemiscal Soceity Japan 43, 2776 (1970).

Presenter: Phan Thi Ngoc-Loan