Erratum: “Azide–water intermolecular coupling measured by two-color two-dimensional infrared spectroscopy” [J. Chem. Phys. 136, 224503 (2012)]

Vibrational correlation between conjugated carbonyl and diazo modes studied by single- and dual-frequency two-dimensional infrared spectroscopy

“…This posted a technical challenge for us in this study because the dispersed pump-probe signal was too weak to allow proper phase adjustment at large T. To this end, it would be advantageous to adopt a collinear pulse pair pump-probe geometry so that phasing is automatically achieved. [34,59] It would also be useful to retain the capability of measuring R and NR spectra individually because the NR spectrum can reveal closely spaced spectral features as we demonstrated here. Pulse shaping with phase cycling can achieve both, and therefore should find nice application in future dual-frequency 2D IR studies.…”

“…Single-color 2D IR method is not applicable to measure the correlation, for example, between the O-H stretching and H-O-H bending modes of water. To circumvent this problem, one needs to use dual-frequency 2D IR spectroscopy [18][19][20][21][22]33,34] in which two mid-IR sources can be tuned independently to excite distinct modes. Due to technical difficulties only a few groups conducted dual-frequency 2D IR measurements so far.…”

“…[22] Other interesting studies using dual frequency pump-probe spectroscopy were also reported recently. [33,34] In this paper, we apply dual-frequency 2D IR spectroscopy to measure the response of two vibrational modes in a conjugated double bond system and investigate whether there is any frequency correlation between them that is caused by valence bond resonances. A good compound for this purpose is ethyl diazoacetate (EDA).…”

Anharmonicities and coherent vibrational dynamics of phosphate ions in bulk H2O

“…While the equilibrium structures of these systems have been well characterized [8][9][10][11] , an understanding of their biological function requires the knowledge of their microscopic interactions with the fluctuating environment through electric fields and hydrogen bonding, i.e., the ultrafast dynamics on the femto-to picosecond time scale of molecular motions. Two-dimensional infrared (2D IR) spectroscopy which combines chemical selectivity with a (sub-)100 fs time resolution and computer simulations have been successfully applied to study these phenomena in water [12][13][14] , DNA [15][16][17] , proteins [18][19][20][21] and ion-water interactions [22][23][24][25][26][27] . The results show that the understanding of intra-and intermolecular couplings provides unique insight into structural dynamics and energy relaxation pathways.…”

Acid–base equilibrium dynamics in methanol and dimethyl sulfoxide probed by two-dimensional infrared spectroscopy

“…2DIR spectroscopy, which is an ultrafast vibrational analog of twodimensional nuclear magnetic resonance (2D NMR), has been extensively used to elucidate fundamentally important molecular processes, such as solute-solvent complexation, 1,2 carbon-carbon rotation, 3 hydrogen-bond switching dynamics in aqueous solutions, 4-8 ligand exchange, 9 ion pair dimerization, 10 ion pairing dynamics in electrolyte solutions, 11,12 intra-and intermolecular vibrational population dynamics [13][14][15][16][17][18][19] and structural dynamics in solutions. Under thermal equilibrium conditions, an acid (HA) dissociates into a proton (H + ) and its conjugate base (A À ) while the conjugate base is protonated to form HA.…”