Molecular Femtosecond Quantum Dynamics Between Less than Yoctoseconds and More than Days: Experiment and Theory

Global Analytical Potential Energy Surfaces for High‐resolution Molecular Spectroscopy and Reaction Dynamics

“…A wave number difference related to an inaccuracy on the order of 100 cm −1 of a vibrational term value corresponds to one of the fastest experimentally known timescales for the redistribution of vibrational energy (300 fs, Marquardt et al 1986, Quack 1995, which has been confirmed by the explicit calculation of the wave packet motion in configuration space on realistic model potentials (Marquardt 1989, Marquardt and. Inaccuracies in this order of magnitude may show up in the quantum dynamical calculation of atomic motion on timescales between 0.3 and 1 ps and make them unreliable for longer times.…”

“…The loop formed by the solid and the interrupted arrows on the right-hand side of the scheme illustrates that model potentials can be improved iteratively by intermediate quantum dynamical calculations and comparison with experimental data from spectroscopy and kinetics. Sometimes, it can be of interest to compare experiment and theory at the level of intermediate, effective experimental parameters such as effective hamiltonian parameters with the "spectroscopic constants" from spectroscopy (Quack 1995, 2001: Fundamentals of Rotation-Vibration Spectra; Albert et al 2011: High- and Isotope-selective Infrared Spectroscopy, this handbook). Analytical representations condense the large amount of information needed to characterize a complicated potential energy hypersurface in a set of a few mathematical expressions with a limited number of numerical parameters; under certain circumstances, they may also lead to conceptually new solutions of the rovibrational problem.…”

Stereomutation dynamics in hydrogen peroxide

“…We would claim that our results provide the basis for a ''high resolution spectroscopic'' approach to short time stereomutation tunneling dynamics in H 2 O 2 . This is true to the extent that the Hamiltonian is spectroscopically adjusted [108]. The time resolution that one can claim for such an approach is Dt > 1=ð4pcDmÞ.…”

Molecular Spectra, Reaction Dynamics, Symmetries and Life

“…We shall briefly discuss here some recent results on tunneling hydrogen bond rearrangement and predissociation dynamics [22][23][24][25][26], fast entropy production in the quantum dynamics of femtosecond intramolecular vibrational redistribution in certain functional groups such as the alkyl CH-chromophore [19][20][21], and the stereomutation dynamics in ammonia isotopomers and other compounds in various limits of chiral symmetry breaking [14] [15].…”

“…In a first part (section 2) we shall provide some examples of our experimental spectroscopic approaches to fast molecular reaction dynamics and intramolecular processes (see also [12][13][14][15][16][17][18][19][20][21]). We shall briefly discuss here some recent results on tunneling hydrogen bond rearrangement and predissociation dynamics [22][23][24][25][26], fast entropy production in the quantum dynamics of femtosecond intramolecular vibrational redistribution in certain functional groups such as the alkyl CH-chromophore [19][20][21], and the stereomutation dynamics in ammonia isotopomers and other compounds in various limits of chiral symmetry breaking [14] [15].…”