Related Experiment Video
Updated: May 23, 2026

Measurement of Ultrafast Vibrational Coherences in Polyatomic Radical Cations with Strong-Field Adiabatic Ionization
Published on: August 6, 2018
Ubiquitous nature of multimode vibrational resonances in positron-molecule annihilation
A C L Jones1, J R Danielson, M R Natisin
1Physics Department, University of California, San Diego, La Jolla California 92093, USA.
Abstract:
Positron annihilation on many molecules occurs via positron capture into vibrational Feshbach resonances, with annihilation rates often further enhanced by energy transfer to vibrational excitations weakly coupled to the positron continuum. Data presented here uncover another scenario in which the positron couples directly to a quasicontinuum of multimode vibrational states. A model that assumes excitation and escape from a statistically complete ensemble of multimode vibrations is presented that reproduces key features of the data.
Related Concept Videos
Molecular Spectroscopy: Absorption and Emission
IR Spectroscopy: Molecular Vibration Overview
Stretching vibrations are vibrational motions that occur along the bond line, changing the bond length or distance between two bonded atoms. They are further distinguished as symmetric or asymmetric. In symmetric stretching, the...
¹H NMR: Complex Splitting
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.
Double Resonance Techniques: Overview
Spin decoupling is usually achieved by...
Atomic Nuclei: Magnetic Resonance
Mass Spectrum

