Themed collection Ultrafast chemical dynamics
Ultrafast chemical dynamics
Introduction to the themed issue of PCCP on ultrafast chemical dynamics.
Phys. Chem. Chem. Phys., 2012,14, 6154-6155
https://doi.org/10.1039/C2CP90065C
Ultrafast soft-mode driven charge relocation in an ionic crystal
Transient electron density maps are directly measured by femtosecond X-ray powder diffraction in potassium dihydrogen phosphate (KDP).
Phys. Chem. Chem. Phys., 2012,14, 6156-6159
https://doi.org/10.1039/C2CP24072F
Excited-state dynamics and efficient triplet formation in phenylthiophene compounds
Transient absorption spectroscopy reveals the ultrafast excited-state relaxation dynamics and efficient, picosecond-scale intersystem crossing kinetics of three closely-related phenylthiophene compounds.
Phys. Chem. Chem. Phys., 2012,14, 6211-6218
https://doi.org/10.1039/C2CP23602H
Simulations of X-ray absorption spectra : the effect of the solvent
We perform QM/MM molecular dynamics simulations on [Pt2(P2O5H2)4]4−. This is used to calculate the ground state X-ray absorption spectrum of the complex, showing a significant solvent effect, which has possible important implications for the structural analysis of molecules in solution.
Phys. Chem. Chem. Phys., 2012,14, 9444-9450
https://doi.org/10.1039/C2CP24080G
Dynamics of fluorescence depolarisation in star-shaped oligofluorene -truxene molecules
Fluorescence anisotropy dynamics are measured in star-shaped fluorene molecules. Two processes are observed: a fast 500 fs depolarisation assigned to exciton localisation, and a slower 3–8 ps process associated with energy transfer between arms.
Phys. Chem. Chem. Phys., 2012,14, 9176-9184
https://doi.org/10.1039/C2CP24141B
The Paternò–Büchi reaction: importance of triplet states in the excited-state reaction pathway
The Paternò–Büchi reaction is studied in an isolated molecule with femtosecond time-resolution, using the [2.2]paracyclophane molecular scaffold.
Phys. Chem. Chem. Phys., 2012,14, 8572-8580
https://doi.org/10.1039/C2CP40819H
Ultrafast exciton dynamics after Soret- or Q-band excitation of a directly β,β′-linked bisporphyrin
A comparative transient absorption study of a Zn-porphyrin monomer and its corresponding dimer shows the influence of excitonic coupling on temporal relaxation.
Phys. Chem. Chem. Phys., 2012,14, 8038-8050
https://doi.org/10.1039/C2CP23608G
Band-edge ultrafast pump–probe spectroscopy of core/shell CdSe/CdS rods: assessing electron delocalization by effective mass calculations
Differential transmission of CdSe/CdS nanorod samples with different core sizes was measured, excitation resonant to the core transition. The bleaching ratio between dot and rod transitions increases with dot size.
Phys. Chem. Chem. Phys., 2012,14, 7420-7426
https://doi.org/10.1039/C2CP40439G
The effect of point mutation on the equilibrium structural fluctuations of ferric Myoglobin
Distinct ultrafast equilibrium fluctuations of different ferric haem protein conformational substates are revealed using 2D-IR spectroscopy.
Phys. Chem. Chem. Phys., 2012,14, 7411-7419
https://doi.org/10.1039/C2CP23568D
Photoinduced electron transfer and solvation dynamics in aqueous clusters: comparison of the photoexcited iodide-water pentamer and the water pentamer anion
I−(H2O)5 photoinduced electron transfer: the excited electron detaches rapidly from the iodine atom and is subsequently stabilized by the gradual iodine-driven reorganization of the water cluster moiety.
Phys. Chem. Chem. Phys., 2012,14, 6257-6265
https://doi.org/10.1039/C2CP24099H
Hydration and temperature interdependence of protein picosecond dynamics
Protein dynamics dominate the THz permittivity for T < 265 K showing that motions most dependent on the dynamical transition are on the >1 ps time scale.
Phys. Chem. Chem. Phys., 2012,14, 6375-6381
https://doi.org/10.1039/C2CP23760A
The molecular underpinnings of a solute-pump/solvent -probe spectroscopy: the theory of polarizability response spectra and an application to preferential solvation
The molecular motions singled out by a novel kind of spectroscopy are simulated and identified for the first time.
Phys. Chem. Chem. Phys., 2012,14, 6320-6331
https://doi.org/10.1039/C2CP24127G
Rotational dynamics of thiocyanate ions in highly concentrated aqueous solutions
Rotational dynamics of chaotropic thiocyanate ions in highly concentrated aqueous solutions studied by IR pump–probe spectroscopy.
Phys. Chem. Chem. Phys., 2012,14, 6233-6240
https://doi.org/10.1039/C2CP23749K
Ultrafast IR spectroscopy of polymeric cytosine nucleic acids reveal the long-lived species is due to a localised state
A dark 1nπ* state is observed in UV-excited cytosine polymers and its lifetime is lengthened relative to the monomer.
Phys. Chem. Chem. Phys., 2012,14, 6307-6311
https://doi.org/10.1039/C2CP23774A
Aqueous solvation of amphiphilic solutes: concentration and temperature dependent study of the ultrafast polarisability relaxation dynamics
We report an investigation of aqueous solutions of TMAO and TBA as a function of concentration and temperature using the ultrafast optically heterodyne detected optical Kerr effect.
Phys. Chem. Chem. Phys., 2012,14, 6343-6351
https://doi.org/10.1039/C2CP23806C
Tracking energy transfer from excited to accepting modes: application to water bend vibrational relaxation
The energy flow from a bend-vibrationally excited water molecule in aqueous solution can be followed in molecular detail via a Poisson bracket work and power formulation. The bend energy decay, in red, is associated with a dominant energy transfer to water rotation, rather than to translation.
Phys. Chem. Chem. Phys., 2012,14, 6332-6342
https://doi.org/10.1039/C2CP23555B
The combined effect of cations and anions on the dynamics of water
The reorientation dynamics of water hydrating cations and anions are studied with femtosecond mid-infrared spectroscopy. It is found that ions influence the dynamics of the hydration shells of their counter-ions.
Phys. Chem. Chem. Phys., 2012,14, 6280-6288
https://doi.org/10.1039/C2CP23882A
Investigation of multiple electronic excited state relaxation pathways following 200 nm photolysis of gas-phase imidazole
Ultrafast deactivation of imidazole following UV excitation is investigated experimentally by probing multiple photoproducts.
Phys. Chem. Chem. Phys., 2012,14, 6266-6272
https://doi.org/10.1039/C2CP23533A
Ultrafast internal conversion in a low band gap polymer for photovoltaics: experimental and theoretical study
Exploiting the combination of ultrafast transient absorption measurements (sub-10 fs time resolution) and quantum chemical DFT//TDDFT calculations we investigate the ultrafast dynamics in a low band gap polymer (PCPDTBT) of great interest for organic photovoltaics, rationalizing the internal conversion photophysical processes occurring after photoexcitation.
Phys. Chem. Chem. Phys., 2012,14, 6367-6374
https://doi.org/10.1039/C2CP23917E
Ultrafast spectroscopy with sub-10 fs deep-ultraviolet pulses
Sub-10 fs deep-ultraviolet pulses are utilized in the ultrafast spectroscopy for the first time.
Phys. Chem. Chem. Phys., 2012,14, 6200-6210
https://doi.org/10.1039/C2CP23649D
Photoexcited structural dynamics of an azobenzene analog 4-nitro-4′-dimethylamino-azobenzene from femtosecond stimulated Raman
Schematic potential energy surface for the photoinitiated trans → cis isomerization of 4-nitro-4′-dimethylamino-azobenzene showing the initial dilation of the CNN bend followed by quick torsional motions.
Phys. Chem. Chem. Phys., 2012,14, 6298-6306
https://doi.org/10.1039/C2CP23468H
Vibrational dynamics of acetate in D2O studied by infrared pump–probe spectroscopy
The infrared pump–probe signal of the asymmetric stretching mode in D2O shows an oscillatory component with a wavenumber of 80 cm−1, which is assigned as an intermolecular mode.
Phys. Chem. Chem. Phys., 2012,14, 6359-6366
https://doi.org/10.1039/C2CP23647H
Solvent -dependent activation of intermediate excited states in the energy relaxation pathways of spheroidene
Environment dependence of ultrafast excited state dynamics in spheroidene and appearance of an intermediate state in the case of a low polarizability solvent.
Phys. Chem. Chem. Phys., 2012,14, 6312-6319
https://doi.org/10.1039/C2CP23585D
Femtosecond fluorescence study of the reaction pathways and nature of the reactive S1 state of cis-stilbene
Femtosecond fluorescence of cis-stilbene showed two components from different potential regions and indicated isomerization/cyclization branching occurring before the CC twisting.
Phys. Chem. Chem. Phys., 2012,14, 6225-6232
https://doi.org/10.1039/C2CP23959K
LIAD-fs scheme for studies of ultrafast laser interactions with gas phase biomolecules
A new technique for ultrashort laser studies of biomolecules, liberated into the gas phase via laser induced acoustic desorption (LIAD).
Phys. Chem. Chem. Phys., 2012,14, 6289-6297
https://doi.org/10.1039/C2CP23840C
Ultrafast primary processes of an iron-(III) azido complex in solution induced with 266 nm light
The photodissociation dynamics of azide radicals from an iron complex are studied with femtosecond UV-pump–mid-IR probe spectroscopy.
Phys. Chem. Chem. Phys., 2012,14, 6165-6172
https://doi.org/10.1039/C2CP23435A
Dynamic structures of aqueous oxalate and the effects of counterions seen by 2D IR
Two dimensional vibrational echo and FTIR spectroscopy supported by DFT calculations reveal contact ion pairs in caesium oxalate solutions.
Phys. Chem. Chem. Phys., 2012,14, 6219-6224
https://doi.org/10.1039/C2CP23892F
Photophysics of the galvinoxyl free radical revisited
The galvinoxyl free radical converts 3 eV (70 kcal mol−1) of electronic energy within less than 200 femtoseconds into vibrational energy.
Phys. Chem. Chem. Phys., 2012,14, 6352-6358
https://doi.org/10.1039/C2CP23577C
Ultrafast spin-state photoswitching in a crystal and slower consecutive processes investigated by femtosecond optical spectroscopy and picosecond X-ray diffraction
Ultrafast probes are combined to study spin state photo- switching dynamics in two spin-crossover molecular polymorphs.
Phys. Chem. Chem. Phys., 2012,14, 6192-6199
https://doi.org/10.1039/C2CP23587K
Two-dimensional infrared spectroscopy of neat ice Ih
Isotropic and anisotropic 2D-IR spectra of neat ice Ih, reporting on the couplings that give rise to its peculiar lineshape.
Phys. Chem. Chem. Phys., 2012,14, 6250-6256
https://doi.org/10.1039/C2CP23710E
Femtosecond dynamics of cyclopropenylidene , c-C3H2
The B 1B1 state of c-C3H2 has been investigated by femtosecond time-resolved photoelectron spectroscopy.
Phys. Chem. Chem. Phys., 2012,14, 6173-6178
https://doi.org/10.1039/C2CP23728H
Discrimination between coupling networks of glucopyranosides varying at a single stereocenter using two-dimensional vibrational correlation spectroscopy
Two-dimensional infrared correlation spectra show significant differences in the coupling networks of anomers that vary at a single stereochemical center.
Phys. Chem. Chem. Phys., 2012,14, 6179-6191
https://doi.org/10.1039/C2CP23245F
Time-dependent quantum dynamical simulations of C2 condensation under extreme conditions
Quantum dynamical simulations of carbon vapor show that nonadiabatic electronic stopping leads to fast aggregation of C2 molecules into carbon nanostructures.
Phys. Chem. Chem. Phys., 2012,14, 6273-6279
https://doi.org/10.1039/C1CP22035G
H-abstraction is more efficient than cis–trans isomerization in (4-methylcyclohexylidene) fluoromethane . An ab initio molecular dynamics study
Ab initio molecular dynamics is used to unravel the different pathways that (4-methylcyclohexylidene) fluoromethane undergoes after light irradiation.
Phys. Chem. Chem. Phys., 2012,14, 6241-6249
https://doi.org/10.1039/C1CP22646K
Ultrafast vibrational energy relaxation of the water bridge
Femtosecond mid-infrared spectroscopy is used to study the vibrational relaxation of water molecules constituting a so-called water bridge.
Phys. Chem. Chem. Phys., 2012,14, 6160-6164
https://doi.org/10.1039/C1CP22358E
About this collection
PCCP is delighted to present a collection of articles on the theme of ultrafast chemical dynamics, Guest Edited by Klaas Wynne (University of Glasgow, UK) and Neil T. Hunt (University of Strathclyde, UK).