Related Experiment Video
Updated: Jul 15, 2026

Measurement of Ultrafast Vibrational Coherences in Polyatomic Radical Cations with Strong-Field Adiabatic Ionization
Published on: August 6, 2018
Photodissociation dynamics of AgH in the ultraviolet: Rovibrationally resolved shape resonances
Yu Wang1, Lin Jiang1, Xing-Guang Su2
1Shanxi Province Engineering Research Center of Precision Measurement and Online Detection Equipment, School of Applied Science, Taiyuan University of Science and Technology, Taiyuan, 030024, China.
None:
Ultraviolet photodissociation of AgH is investigated by full quantum calculations for transitions from the ground X1Σ+ state to the A1Σ+, 31Σ+, 11Π, and 21Π excited states. Adiabatic potential energy curves and transition dipole moments obtained at the icMRCI+Q level are used to determine rovibrationally resolved and local thermodynamic equilibrium (LTE) averaged cross sections. The calculated excited-state potentials show no pronounced avoided crossings in the dissociative region, indicating that the main photodissociation dynamics of AgH can be described within an adiabatic single-channel framework. Pronounced near-threshold rovibrational shape resonances are found in the 11Π and 21Π channels, originating from quasibound levels supported by centrifugal barriers. The state-resolved cross sections exhibit systematic redshifts with increasing vibrational and rotational excitation, while thermal averaging reshapes the spectrum through rovibrational smoothing, long-wavelength extension, and resonance accumulation. The total photodissociation spectrum is governed by wavelength-dependent competition mainly among the 31Σ+, 21Π, and 11Π channels, whereas the A1Σ+ channel remains weak. These results provide the first theoretical photodissociation dataset for AgH and clarify the main physical mechanisms governing its ultraviolet dissociation dynamics.
Related Concept Videos
UV–Vis Spectroscopy: Molecular Electronic Transitions
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...
Deactivation Processes: Jablonski Diagram
IR Spectroscopy: Hooke's Law Approximation of Molecular Vibration
According to Hooke's law, the vibrational frequency is directly proportional to the...
Molecular Spectroscopy: Absorption and Emission
IR and UV–Vis Spectroscopy of Aldehydes and Ketones

