Related Experiment Video
Updated: Jun 10, 2026
10:52
Direct Imaging of Laser-driven Ultrafast Molecular Rotation
Published on: February 4, 2017
Two-proton migration in 1,3-butadiene in intense laser fields
Huailiang Xu1, Tomoya Okino, Katsunori Nakai
1Department of Chemistry, School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
Physical Chemistry Chemical Physics : PCCP
|August 24, 2010
Summary
Ultrafast proton migration in 1,3-butadiene was observed using intense laser fields. Two protons migrate within the molecule before its three-body decomposition, as shown by Coulomb explosion imaging.
Area of Science:
- Chemical Physics
- Molecular Dynamics
- Laser-Induced Reactions
Background:
- Understanding molecular behavior under extreme conditions is crucial.
- Proton migration dynamics in organic molecules are complex.
- Intense laser fields provide a unique environment to study ultrafast processes.
Purpose of the Study:
- To investigate ultrafast proton migration in 1,3-butadiene.
- To elucidate the pathways of proton migration and subsequent molecular decomposition.
- To characterize the dynamics of 1,3-butadiene under intense laser irradiation.
Main Methods:
- Coulomb explosion coincidence momentum imaging was employed.
- Intense laser fields (40 fs, 4.5 × 10^14 W cm^-2) were used.
- Spatial distribution maps of migrating protons were reconstructed.
Main Results:
- Evidence of ultrafast proton migration within 1,3-butadiene was observed.
- Two distinct three-body Coulomb explosion pathways were identified: C(4)H(6)(3+)→ H(+) + CH(3)(+) + C(3)H(2)(+) and C(4)H(6)(3+)→ H(+) + C(2)H(+) + C(2)H(4)(+).
- The study revealed that two protons migrate before the three-body decomposition occurs.
Conclusions:
- Ultrafast proton migration is a key process in 1,3-butadiene under intense laser fields.
- The observed pathways provide insights into the fragmentation mechanisms.
- This research contributes to the understanding of molecular fragmentation dynamics.
Related Concept Videos
01:24π Molecular Orbitals of 1,3-Butadiene
Conjugated dienes have lower heats of hydrogenation than cumulated and isolated dienes, making them more stable. The enhanced stabilization of conjugated systems can be understood from their π molecular orbitals.
The simplest conjugated diene is 1,3-butadiene: a four-carbon system where each carbon is sp2-hybridized and has an unhybridized p orbital that contains an unpaired electron. According to molecular orbital theory, atomic orbitals combine to form molecular orbitals such that the number...
The simplest conjugated diene is 1,3-butadiene: a four-carbon system where each carbon is sp2-hybridized and has an unhybridized p orbital that contains an unpaired electron. According to molecular orbital theory, atomic orbitals combine to form molecular orbitals such that the number...
01:13¹H NMR: Complex Splitting
A proton M that is coupled to a proton X results in doublet signals for M. However, NMR-active nuclei can be simultaneously coupled to more than one nonequivalent nucleus. When M is coupled to a second proton A, such as in styrene oxide, each peak in the doublet is split into another doublet.
Splitting diagrams or splitting tree diagrams are routinely used to depict such complex couplings. While drawing splitting diagrams, the splitting with the larger coupling constant is usually applied first.
Splitting diagrams or splitting tree diagrams are routinely used to depict such complex couplings. While drawing splitting diagrams, the splitting with the larger coupling constant is usually applied first.
01:08Spin–Spin Coupling Constant: Overview
In bromoethane, the three methyl protons are coupled to the two methylene protons that are three bonds away. In accordance with the n+1 rule, the signal from the methyl protons is split into three peaks with 1:2:1 relative intensities. The methylene protons appear as a quartet, with the relative intensities of 1:3:3:1.
Qualitatively, any spin plus-half nucleus polarizes the spins of its electrons to the minus-half state. Consequently, the paired electron in the hydrogen–carbon bond must have a...
Qualitatively, any spin plus-half nucleus polarizes the spins of its electrons to the minus-half state. Consequently, the paired electron in the hydrogen–carbon bond must have a...
01:32UV–Vis Spectroscopy of Conjugated Systems
Organic compounds with conjugated double bonds show strong absorption features in the UV–visible region of the electromagnetic spectrum attributed to π → π* electronic excitations. Generally, a UV–vis absorption spectrum is recorded as a plot of absorbance vs wavelength. The wavelength of maximum absorbance, which manifests as a peak in the absorption spectrum, is denoted as λmax.
One of the factors influencing λmax is the extent of conjugation in the...
One of the factors influencing λmax is the extent of conjugation in the...
01:07Proton (¹H) NMR: Chemical Shift
Organic molecules primarily contain carbon and hydrogen atoms. While all the hydrogen isotopes are NMR-active, protium or hydrogen-1 is the most abundant. It has a significant energy separation between its nuclear spin states due to its large gyromagnetic ratio. As per Boltzmann's distribution, an increase in the energy separation implies a greater excess population of nuclei available for excitation, resulting in a strong NMR absorption signal.
Absorption signals of all the protium nuclei in a...
Absorption signals of all the protium nuclei in a...
00:48¹H NMR of Labile Protons: Deuterium (²H) Substitution
This lesson illustrates the role of deuterium substitution in simplifying the NMR spectrum of compounds comprising labile protons. One method employed is the use of deuterium. Amongst the three isotopes of hydrogen, deuterium (2H) has a nucleus composed of one proton and one neutron. When the D2O solvent is added to a pure dry ethanol solution, its labile proton is substituted with deuterium.