RT Journal Article
T1 Stark control of multiphoton ionization through Freeman resonances in alkyl iodides
A1 Casasús, Ignacio
A1 Corrales, María
A1 Murillo Sánchez, Marta Luisa
A1 Marggi Poullaín, Sonia
A1 Oliveira, Nelson de
A1 Limão-Vieira, Paulo
A1 Bañares Morcillo, Luis
AB Multiphoton ionization (MPI) of alkyl iodides (RI, R = CnH2n+1, n = 1–4) has been investigated with femtosecond laser pulses centered at 800 and 400 nm along with photoelectron imaging detection. In addition, the ultraviolet (UV)–vacuum ultraviolet (VUV) absorption spectra of gas-phase RIs have been measured in the photon energy range of 5–11 eV using the VUV Fourier transform spectrometer at the VUV DESIRS beamline of the synchrotron SOLEIL facility. The use of high-laser-field strengths in matter–radiation interaction generates highly non-linear phenomena, such as the Stark shift effect, which distorts the potential energy surfaces of molecules by varying both the energy of electronic and rovibrational states and their ionization energies. The Stark shift can then generate resonances between intermediate states and an integer number of laser photons of a given wavelength, which are commonly known as Freeman resonances. Here, we study how the molecular structure of linear and branched alkyl iodides affects the UV–VUV absorption spectrum, the MPI process, and the generation of Freeman resonances. The obtained results reveal a dominant resonance in the experiments at 800 nm, which counter-intuitively appears at the same photoelectron kinetic energy in the whole alkyl iodide series. The ionization pathways of this resonance strongly involve the 6p( 2 E3/2) Rydberg state with different degrees of vibrational excitation, revealing an energy compensation effect as the R-chain complexity increases
PB AIP American Institute of Physics
SN 0021-9606
YR 2023
FD 2023
LK https://hdl.handle.net/20.500.14352/92940
UL https://hdl.handle.net/20.500.14352/92940
LA eng
NO Ignacio M. Casasús, María E. Corrales, Marta L. Murillo-Sánchez, Sonia Marggi Poullain, Nelson de Oliveira, Paulo Limão-Vieira, Luis Bañares; Stark control of multiphoton ionization through Freeman resonances in alkyl iodides. J. Chem. Phys. 21 August 2023; 159 (7): 074302. https://doi.org/10.1063/5.0161628
DS Docta Complutense
RD 6 abr 2025