Related Experiment Video
Updated: Jul 19, 2026

Direct Imaging of Laser-driven Ultrafast Molecular Rotation
Published on: February 4, 2017
Explosive photodissociation of methane induced by ultrafast intense laser
Fanao Kong1, Qi Luo, Huailiang Xu
1Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, People's Republic of China. kong@iccas.ac.cn
Abstract:
A new type of molecular fragmentation induced by femtosecond intense laser at the intensity of 2 x 10(14) W/cm2 is reported. For the parent molecule of methane, ethylene, n-butane, and 1-butene, fluorescence from H (n = 3-->2), CH (A 2Delta, B 2Sigma-, and C 2Sigma+-->X 2Pi), or C2 (d 3Pi g-->a 3Pi u) is observed in the spectrum. It shows that the fragmentation is a universal property of neutral molecule in the intense laser field. Unlike breaking only one or two chemical bonds in conventional UV photodissociation, the fragmentation caused by the intense laser undergoes vigorous changes, breaking most of the bonds in the molecule, like an explosion. The fragments are neutral species and cannot be produced through Coulomb explosion of multiply charged ion. The laser power dependence of CH (A-->X) emission of methane on a log-log scale has a slope of 10 +/- 1. The fragmentation is thus explained as multiple channel dissociation of the superexcited state of parent molecule, which is created by multiphoton excitation.
More Related Videos
08:22Measurement of Ultrafast Vibrational Coherences in Polyatomic Radical Cations with Strong-Field Adiabatic Ionization
Published on: August 6, 2018
09:40Measurement and Analysis of Atomic Hydrogen and Diatomic Molecular AlO, C2, CN, and TiO Spectra Following Laser-induced Optical Breakdown
Published on: February 14, 2014
Related Concept Videos
Chemical Ionization (CI) Mass Spectrometry
Mass Spectrum
Mass Spectrometry: Molecular Fragmentation Overview
One type of fragmentation pattern is the cleavage of a single bond in the molecular ion. The cleavage leads to a radical and a cation. The cleavage can occur at...
Mass Spectrometry: Long-Chain Alkane Fragmentation
Mass Spectrometry: Branched Alkane Fragmentation
Cycloaddition Reactions: MO Requirements for Photochemical Activation