Vibronic Dynamics of Photodissociating ICN from Simulations of Ultrafast X‐Ray Absorption Spectroscopy

Abstract

Ultrafast UV-pump/soft-X-ray-probe spectroscopy is as ubject of great interest since it can provide detailed information about dynamical photochemical processes with ultrafast resolution and atomic specificity.H ere,w ef ocus on the photodissociation of ICN in the 1 P 1 excited state,w ith emphasis on the transient response in the soft-X-ray spectral region as described by the ab initio spectral lineshape averaged over the nuclear wavepacket probability density.W ef ind that the carbon K-edge spectral region reveals ar ich transient response that provides direct insights into the dynamics of frontier orbitals during the I À CN bond cleavage process.T he simulated UV-pump/soft-X-ray-probe spectra exhibit detailed dynamical information, including atime-domain signature for coherent vibration associated with the photogenerated CN fragment.

Dynamic signatures of electronically nonadiabatic coupling in sodium hydride: a rigorous test for the symmetric quasi-classical model applied to realistic, ab initio electronic states in the adiabatic representation

“…However, as these methods scale exponentially with system size they are typically prohibitively expensive for all but the lowest-dimensional chemical systems. [33][34][35] When true quantum mechanical effects, e.g., tunneling, are not too important treating the electronic and/or nuclear DOF with classical mechanics offers an appealing low cost alternative with easily parallelizable trajectories that are directly amenable to electronic structure calculations.…”

Second Linear Response Theory and the Analytic Calculation of Excited-State Properties

“…Obtaining properties associated with exciting electronic excited states is crucial to the understanding and interpretation of the photodynamics of molecules and also their response to external electrical perturbations. It is also crucial for computing transition dipoles between excited states as they are fundamental to the computation of excited-state spectra and multiphoton absorption, − phenomena that are gaining renewed widespread attention due to their connection to quantum entanglement. − In general, nonlinear optical phenomena are important to the design and optimization of molecular dyes, which are increasingly used in sensing applications in medicine and materials science.…”

Dynamic signature of electronically nonadiabatic coupling in sodium hydride: a rigorous test for the symmetric quasi-classical model applied to realistic, ab initio electronic states.

“…17,18 Ideally, one would choose a quantum mechanical-based method for both the electronic and nuclear dynamics, which generally o↵ers the greatest accuracy, but as these methods scale exponentially with system size, they are typically prohibitively expensive for all but the lowest-dimensional chemical systems. [19][20][21] When true quantum mechanical e↵ects, i.e., tunneling, are not too important treating the electronic and/or nuclear DOF with classical mechanics o↵ers an appealing low cost alternative with easily parallelizable trajectories that are directly amenable to electronic structure calculations.…”