title: A Combination of Chemometrics and Quantum Mechanics Methods Applied to Analysis of Femtosecond Transient Absorption Spectrum of Ortho-Nitroaniline.
abstract: A combination of the advanced chemometrics method with quantum mechanics calculation was for the first time applied to explore a facile yet efficient analysis strategy to thoroughly resolve femtosecond transient absorption spectroscopy of ortho-nitroaniline (ONA), served as a model compound of important nitroaromatics and explosives. The result revealed that the ONA molecule is primarily excited to S3 excited state from the ground state and then ultrafast relaxes to S2 state. The internal conversion from S2 to S1 occurs within 0.9 ps. One intermediate state S* was identified in the intersystem crossing (ISC) process, which is different from the specific upper triplet receiver state proposed in some other nitroaromatics systems. The S1 state decays to the S* one within 6.4 ps and then intersystem crossing to the lowest triplet state within 19.6 ps. T1 was estimated to have a lifetime up to 2 ns. The relatively long S* state and very long-lived T1 one should play a vital role as precursors to various nitroaromatic and explosive photoproducts.
authors.affiliation: College of Chemistry, Sichuan University, Chengdu 610064, People's Republic of China.
authors.forename: Jing
authors.initials: J
authors.lastname: Yi
authors.affiliation: Institute of Chemical Material, China Academy of Engineering Physics (CAEP), Mianyang 621900, People's Republic of China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Xiong
authors.affiliation: Institute of Chemical Material, China Academy of Engineering Physics (CAEP), Mianyang 621900, People's Republic of China.
authors.forename: Kemei
authors.initials: K
authors.lastname: Cheng
authors.affiliation: College of Chemistry, Sichuan University, Chengdu 610064, People's Republic of China.
authors.forename: Menglong
authors.initials: M
authors.lastname: Li
authors.affiliation: Science and Technology on Plasma Physics Laboratory, Research Center of Laser Fusion, CAEP, Mianyang 621900, People's Republic of China.
authors.forename: Genbai
authors.initials: G
authors.lastname: Chu
authors.affiliation: College of Chemistry, Sichuan University, Chengdu 610064, People's Republic of China.
authors.forename: Xuemei
authors.initials: X
authors.lastname: Pu
authors.affiliation: Institute of Chemical Material, China Academy of Engineering Physics (CAEP), Mianyang 621900, People's Republic of China.
authors.forename: Tao
authors.initials: T
authors.lastname: Xu