2026-10-09T19:41:48Z https://api.figshare.com/v2/oai

oai:figshare.com:article/33981262 2026-09-28T07:47:55Z category_25270 category_25261 portal_379 item_type_3 month_year_09_2026

Isomerization HCN → HNC in the electronic ground state using chirp-optimized mid-IR laser pulses: 4D quantum dynamics Niels Engholm Henriksen (6211961) Kasper Linger Effersø (11769230) Theoretical and computational chemistry not elsewhere classified Radiation and matter HCN Isomerization Quantum Dynamics Coherent Control Femtosecond Laser <p dir="ltr">The laser-induced isomerization of HCN is studied starting from a four-nuclear-degrees-of-freedom (4D) Hamiltonian, which includes the rotation (χ) of H around a fixed CN axis. This Hamiltonian reproduces the known exact quantized rovibrational states, including Coriolis coupling. We study the laser-induced dynamics using linearly chirped mid-IR laser pulses with a temporal duration of ≃ 1 picosecond. The initial state is the vibrational ground state of HCN with J = K = 0, where K is the quantum number associated with vibrational angular momentum and the rotation of H around the CN axis. Over-barrier excitation via fundamental or first overtone bending modes is studied. An optimized pump-dump pulse, which is fully tailored for a fixed χ angle is also employed and leads to considerable isomerization. Multiphoton excitation via the fundamental bending mode creates a rotational wave packet in the χ angle, whereas multiphoton excitation via the overtone bending mode preserves the uniform distribution in χ. The influence of the χ angle on the isomerization yield is discussed in a comparison with a planar 3D model of the isomerization.</p> 2026-09-28T07:47:55Z Dataset Dataset 10.11583/DTU.33981262.v1 https://figshare.com/articles/dataset/Isomerization_HCN_HNC_in_the_electronic_ground_state_using_chirp-optimized_mid-IR_laser_pulses_4D_quantum_dynamics/33981262 CC BY 4.0