Showing papers in "Chemical Physics in 1999"

TL;DR: In this article, the concept of ratiometric identification and separation of sub-populations of single biomolecules which are labeled with individual fluorophores and are freely diffusing (or flowing) through the laser excitation volume is introduced.

TL;DR: In this article, surface-enhanced hyper-Raman scattering and surfaceenhanced anti-Stokes Raman scattering were studied as potential tools for nonlinear single-molecule Raman spectroscopy.

TL;DR: In this paper, the photodynamical behavior of wild-type (WT) and a F64L S65T mutant (BioST) of GFP was investigated in the microsecond to millisecond time-range.

TL;DR: The distributions indicate that single molecule GCN4-Pf is in dynamic folding equilibrium with the position of the equilibrium being altered by the concentration of urea.

TL;DR: In this article, a theoretical study of the fluorescence emission properties of a single dye molecule near a metal film is presented, and it is shown that despite the high fluorescence quenching rates, the increased photostability of the molecule makes spectroscopic studies on single-molecule level feasible.

TL;DR: It is demonstrated that it is possible to detect the assembly–disassembly of individual protein molecules as well as conformational changes occurring within a single protein molecule.

TL;DR: In this article, the protonation kinetics of fluorescein isothiocyanate (FITC) and a F64L S65T variant (BioST) of green fluorescent protein (GFP) has been investigated using fluorescence correlation spectroscopy (FCS) and it is shown that buffer effects, in general, must be considered when using fluorescent species as pH-probes and that the pH behaviour of BioST, in contrast to that of FITC, cannot be modelled as a single-step reaction.

TL;DR: Using matrix-isolation infrared spectroscopy, 532 nm pulsed laser ablation of Ta2O5 and Ta targets in O2/Ar gas ambient has been investigated as mentioned in this paper.

TL;DR: In this paper, the spectral densities of cyclic H-bonded dimers are obtained in a full quantum mechanical way by introducing relaxation effects towards the surroundings in the model of Wojcik [Mol. Phys. 36 (1978) 1757] which accounts for the possibility of simultaneous Davydov coupling and Fermi coupling (between each hydrogen bond and one or several bending modes).

TL;DR: In this paper, a series of soluble push-pull diphenyl polyenes of increasing length and having various donor (D) and acceptor (A) end groups have been synthesized and investigated.

TL;DR: In this paper, a femtosecond transient absorption spec- troscopy was used to investigate the reaction dynamics of photochromic ring-opening reaction of 1,2-bis 5-formyl-2-methyl-thien-3-yl perfluoro.

TL;DR: In this article, the structural change of liquid water induced by an external electric field was analyzed using molecular dynamics simulations with the rigid TIP4P water model, and the threshold for significant structural change is thought to be between 0.2 and 0.15 V/A.

TL;DR: In this paper, the fluorescence quantum distributions, quantum yields, degrees of polarisation, and stimulated emission cross-section spectra of four para-phenylene vinylene and two paraphenylene ethynylene luminescent polymers were determined.

TL;DR: The structure and relative energies of L-alanyl-L-alanine (LALA) in the presence of explicit water molecules have been determined by using the density functional theory (DFT) Becke3-Lee-Yang-Parr functional and the 6-31G* basis set.

TL;DR: In this paper, the accuracy of different theoretical approaches to uranyl reduction is compared at the SCF and different correlated levels, including density functional methods, for geometries and reaction energies.

TL;DR: In this article, the authors used the ab initio approach employing the 4-31G basis set for all the atoms except the amino group of cytosine for which the 6-311+G * basis set was used.

TL;DR: In this article, the vibrational analysis of a set of o -hydroxybenzoyl compounds (salicylaldehyde, o-hydroxyacetophenone, methyl salicylate and salicylamide) has been performed by infrared (IR) measurements and by quantum chemical calculations using B3LYP density functional in conjunction with 6-31G ∗∗ and 6-311++G(3df, 2p) basis sets.

TL;DR: In this article, the two-state model for push-pull polyenes is extended to account for the coupling of electrons with adiabatic vibrations, and for the interaction with the solvent, modeled in terms of a reaction field.

TL;DR: In this paper, the results of semi-empirical quantum-chemical calculations of the first and second-order hyperpolarizabilities (β and γ, respectively) for molecules in the gas phase and in chloroform and aqueous solvents are presented.

TL;DR: In this article, the relative variation of β e and β v in D/A (NH 2 /NO 2 ) substituted π-conjugated compounds as a function of the specific nature, length, and charge of the linker was studied.

TL;DR: In this article, the results of density functional theory (DFT) studies with various exchange-correlation functionals such as the local density functional SL, the non-local density functional BLYP, the hybrid functional B3LYP, and the half-and-half functional BHandH, using the 6-31G ∗, 6- 31+G ∆, and 6 -31G∆ basis sets, were presented as the results.

TL;DR: Nagard et al. as mentioned in this paper developed and tested model potentials for the gas-solid interaction by comparing experimental and simulated angular distributions for different translational energies (0.09-0.8 eV), incident angles (30-75°) and surface temperatures (300-1200 K).

TL;DR: In this paper, the basic photophysical parameters of a terrylene host/guest system such as photostability, single-molecule emission rates and the properties of dispersed fluorescence spectra are reported.

TL;DR: In this paper, a Monte Carlo simulation of liquid methanol was performed in NVT ensemble at 298 K using a cubic simulation box containing 500 molecules, where the number of linked molecules, formation of branches and cyclic structures were evaluated.

TL;DR: In this paper, the molecular masses of polyene-like molecules with very long conjugation length (N up to 1100 carbon-carbon double bonds) were determined using the MALDI-TOF technique.

TL;DR: In this article, a detailed spectroscopic study of the optical characteristics of the tetrahedrally coordinated Cr4+ ion in LiAlO2 and LiGaO2 is given.

TL;DR: In this article, the potentials for the ground state and several low-lying excited states of the cadmium atom interacting with He, Ne, Ar, Kr and Xe have been obtained from valence ab-initio CASSCF/CASPT2 calculations.

TL;DR: In this paper, a theoretical analysis of the first-order hyperpolarizability properties (β) of polyenic molecules of octupolar C3h symmetry (polyenoctupoles), based on CNDO/S calculations, and interpreted in the frame of a tensorial formalism, is presented.

TL;DR: In this article, fluorescence-excitation spectra from the B800 absorption band of individual light-harvesting complexes (LH2) of purple bacteria at 1.2 K were recorded.

TL;DR: In this article, the first low-lying excited states of plutonium, Pu(VI)O 2 2+, were optimized and found to be basically unchanged due to the local character of the excitations.