Rotational and vibrational dynamics in the excited electronic state of deprotonated and protonated fluorescein studied by time-resolved photofragmentation in an ion trap
نویسندگان
چکیده
Excited state dynamics of deprotonated and protonated fluorescein were investigated by polarization dependent femtosecond time-resolved pump-probe photofragmentation in a 3D ion trap. Transients of deprotonated fluorescein exhibit vibrational wavepacket dynamics with weak polarization dependence. Transients of protonated fluorescein show only effects of molecular alignment and rotational dephasing. The time resolved rotational anisotropy of protonated fluorescein is simulated by the calculated orientational correlation function. The observed differences between deprotonated and protonated fluorescein are ascribed to their different higher lying electronically excited states and corresponding structures. This is partially supported by time-dependent density functional theory calculations of the excited state structures.
منابع مشابه
Probing the vibrational spectroscopy of the deprotonated thymine radical by photodetachment and state-selective autodetachment photoelectron spectroscopy via dipole-bound states† †Electronic supplementary information (ESI) available. See DOI: 10.1039/c5sc00704f
Deprotonated thymine can exist in two different forms, depending on which of its two N sites is deprotonated: N1[T–H] or N3[T–H] . Here we report a photodetachment study of the N1[T–H] isomer cooled in a cryogenic ion trap and the observation of an excited dipole-bound state. Eighteen vibrational levels of the dipole-bound state are observed, and its vibrational ground state is found to be 238 ...
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متن کاملProbing the vibrational spectroscopy of the deprotonated thymine radical by photodetachment and state-selective autodetachment photoelectron spectroscopy via dipole-bound states.
Deprotonated thymine can exist in two different forms, depending on which of its two N sites is deprotonated: N1[T-H]- or N3[T-H]-. Here we report a photodetachment study of the N1[T-H]- isomer cooled in a cryogenic ion trap and the observation of an excited dipole-bound state. Eighteen vibrational levels of the dipole-bound state are observed, and its vibrational ground state is found to be 23...
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