Inside front cover
Hydrogen bonding of excited states in supramolecular host–guest inclusion complexes
This Perspective article examines the effect of hydrogen bonding on excited state guests included within molecular hosts in solutions, and the impacts on inclusion complex stability and guest fluorescence.
Hydrogen bonding and reactivity of
water to azines in their S1 (n,π*) electronic excited states in the gas phase and in solution
Possible photochemical and photophysical processes following (n,π*) excitation of azines.
Excited state dynamics and catalytic mechanism of the light-driven enzyme
We review spectroscopic investigations that have been used to study the excited state dynamics and catalytic mechanism of protochlorophyllide oxidoreductase.
The role of hydrogen bonding in excited state intramolecular charge transfer
In the condensed phase H-bond strengthening promotes the formation of the ICT state, in the gaseous phase it may be the H-bond breaking.
Excited state intramolecular
proton transfer (ESIPT): from principal photophysics to the development of new chromophores and applications in fluorescent molecular probes and luminescent materials
The principal photophysics and applications of ESIPT in fluorescent molecular probes and white light-emitting materials are summarized.
Effect of hydrogen-bonding on the excited-state reactivity of
fullerene derivatives and its impact on the control of the emission polarisation from photopolic single crystals
Hydrogen bonding directs the formation of photoactive fullerene ribbons in the solid-state crystal structure of a fullerene derivative resulting in photopolic behaviour.
Ab initio study of the
solvent H-bonding effect on ESIPT reaction and electronic transitions of 3-hydroxychromone derivatives
Ab initio studies of 3-hydroxychromones show that their proton transfer (ESIPT) can be controlled thermodynamically or kinetically by H-bonding.
Structural tuning intra- versus inter-molecular proton transfer reaction in the excited state
A series of the 2-pyridyl-pyrazole derivatives 1–4 possessing five-membered ring hydrogen bonding configuration are synthesized, the structural flexibility of which is strategically tuned to be in the order of 1 > 2 > 3 > 4.
Strategic emission color tuning of highly fluorescent
imidazole-based excited-state intramolecular proton transfer molecules
Via a systematic design and synthesis of the excited-state intramolecular proton-transfer system, the proton-transfer emission can be extensively tuned from 450 nm (HPI) to 630 nm (HPNO).
Photoreaction channels of the guanine–cytosine base pair explored by long-range corrected TDDFT calculations
Potential energy profiles are compared for potentially competing photoinduced processes in the hydrogen-bonded guanine–cytosine base pair, including nonradiative decay in each base and proton transfer between the bases.
anaesthetic–receptor interaction: a combined spectroscopic and computational study of propofol⋯phenol
Propofol–phenol clusters are characterised as a model system of the propofol–tyrosine interaction with the GABAA receptor.
Hydrated alizarin complexes: hydrogen bonding and
The hydrogen bonding structures and proton transfer in both the electronic excited and ground states were studied for the hydration complexes of alizarin as a model system for acid–base indicators.
Hydrogen bond dynamics in the excited states: Photodissociation of
phenol in clusters
Phenol clusters of various complexities were studied both experimentally and theoretically revealing the solvation effects on their photochemistry.
The effect of hydrogen bonding on the excited-state proton transfer in
2-(2′-hydroxyphenyl)benzothiazole: a TDDFT molecular dynamics study
Excited state proton transfer in HBT–water clusters showing triple proton transfer.
proton transfer in strongly enhanced GFP (sGFP2)
Ground- and excited-state proton transfer was studied by pump–dump–probe spectroscopy combined with target analysis, and super-resolution microscopy application is discussed.
Nonradiative decay dynamics of
methyl-4-hydroxycinnamate and its hydrated complex revealed by picosecond pump–probe spectroscopy
Hydrogen-bonding to the phenolic OH dramatically decelerates the trans to cis isomerization rate of methyl 4-hydroxycinnamate (OMpCA). The isomerization barrier height of the OMpCA–water complex is estimated to be ∼500 cm−1.
Experimentally measured permanent dipoles induced by hydrogen bonding. The Stark
spectrum of indole–NH3
The S0 and S1 permanent dipoles of the indole–NH3 complex reveal a substantial contribution from local hydrogen bonding effects, as evidenced by the large induced dipole measured for each electronic state.
Water-wire catalysis in photoinduced acid–base reactions
Femtosecond-resolved spectroscopy reveals that a water wire plays a catalytic role in aqueous acid–base reactions.
electron transfer between various coumarin analogues and N,N-dimethylaniline inside niosome, a nonionic innocuous polyethylene glycol-based surfactant assembly
Electron transfer study inside bio-mimicking organized media like niosome helps understanding various chemical reactions occurring in natural biological systems.
Solvent effects on electron-driven proton-transfer processes: adenine– thymine base pairs
TD-DFT computations confirm barrier-less Electron-Driven Proton Transfer in an Adenine–Thymine Watson–Crick complex in the gas phase, suggesting also that both EDPT and the possible radiation-less deactivation to the ground state are strongly influenced by environmental effects.
The photo-dissociation of the
pyrrole–ammonia complex—the role of hydrogen bonding in Rydberg states photochemistry
Two hydrogen-bonded Rydberg type species are located on the lowest excited singlet PES. The Rydberg center shift (RCS) mechanism proposed that the Rydberg orbital could be located on either the pyrrole or the ammonia components of the cluster. The proton shift is escorted by a shift of the Rydberg orbital, according to the new proton location.
H-bonded network rearrangements in the S0, S1 and D0 states of neutral and cationic p-cresol(H2O)(NH3) complexes
Different H-bonded network rearrangements are observed in the S0, S1 and D0 states of neutral and cationic p-cresol(H2O)(NH3) complexes.
proton transfer in N-methyl-6-hydroxyquinolinium salts: solvent and temperature effects
The ultrafast kinetics and temperature dependence of the excited-state proton transfer (ESPT) of the “super” photoacid N-methyl-6-hydroxyquinolinium was studied and compared with those of another “super”photoacid 5,8-dicyano-2-naphthol.
Hydrogen bond effects in the ground and excited singlet states of 4H-1-benzopyrane-4-thione in water—theory and experiment
Hydrogen bonding in the ground and electronically excited singlet states of thioketone.
Spectral deciphering of the interaction between an intramolecular hydrogen bonded ESIPT
drug, 3,5-dichlorosalicylic acid, and a model transport protein
The present study reports the binding interaction of an ESIPT drug with a model transport protein BSA with insights into structure, functionality of the protein and drug binding pharmacokinetics behavior.
On the fluorescence of
methyl salicylate: the significance of its IMHB
Photophysical diagram proposed to describe the behaviour of the normal molecular structure of methylsalycilate.
Excited-state hydrogen relay along a blended-alcohol chain as a model system of a
proton wire: deuterium effect on the reaction dynamics
The rate constant of excited-state deuteron relay along a hydrogen-bonded blended-alcohol chain is determined mostly by the acidity of the alcohol molecule participating directly in the rate-determining step.
About this collection
PCCP is delighted to present a themed issue onHydrogen bonding in electronically excited states
, Guest Edited by Guang-Jiu Zhao and Ke-Li Han (Dalian Institute of Chemical Physics, China). The issue focuses on hydrogen bonding in electronically excited states, which plays an increasingly important role in many photo-physical processes and photochemical reactions.