Attosecond Molecular Dynamics and Spectroscopy

Perspectives on parity violation in chiral molecules: theory, spectroscopic experiment and biomolecular homochirality

“…We can note here the recent efforts on probing chirality on the femtosecond time scale. 147,148 Also, on short time scales, vibrational excitation even of achiral molecules can show time dependent chirality, following the motion, say, of a quasiharmonic coherent oscillator state of an antisymmetric normal mode. 61,149,150 Fig.…”

Equation-of-Motion Methods for the Calculation of Femtosecond Time-Resolved 4-Wave-Mixing and N-Wave-Mixing Signals

“…In the weak system−field coupling limit, P(t) is dominated by the linear response P (1) (t) (if it exists in the phasematching direction k under consideration) or by the lowestorder nonlinear response, which usually is given by the thirdorder polarization P (3) (t). If the system−field coupling exceeds a certain critical value, 550 P (5) (t), P (7) (t), etc. start to substantially contribute to P(t).…”

“…Time-resolved X-ray spectroscopy also delivers information on electron-vibrational dynamics but employs core-excited states as the reporter states, instead of valence-excited states in UV/vis spectroscopy. 3−5 Attosecond time-resolved spectroscopy addresses primarily the dynamics of electrons on time scales at which atomic nuclei are essentially stationary 6,7 (the impact of nuclear motion on the detected transients is not always negligible though 8,9 ). Timeresolved nonlinear IR spectroscopy, on the other hand, explores the evolution of coupled vibrational modes in the electronic ground state.…”

RhoDyn: A ρ-TD-RASCI Framework to Study Ultrafast Electron Dynamics in Molecules

“…The past decade heralds the gradual change of the ultrafast paradigm in physics and chemistry from the femtosecond to subfemtosecond and even a few tens of attoseconds domain. The fascinating growth in the number of studies of the ultrafast phenomena is owing to establishing new sources such as X-ray free electron lasers (XFELs) − and high harmonics generation (HHG) setups , which give access to dynamics at electronic time scales. − State-of-the-art XFELs allow studying processes with extremely intense ultrashort pulses enabling studies of multiple ionization and radiation damage. , HHG, in turn, gives unparalleled pulse durations of several tens of attoseconds and thus enables unprecedented experiments on electronic structure, such as imaging of molecular orbitals, − attosecond interferometry, , measuring phases of photoionization amplitudes, , and others. Moreover, one of the most intriguing phenomena in ultrafast physics and chemistry, charge migration (CM), , already has impressive experimental evidence. − …”