Experimental determination of the effect of polarization of the heating laser pulse on the characteristic decay time constant and focal length of thermal lenses, and on the thermal diffusivities in pure liquids

Nonradiative Relaxation Processes and Electronically Excited States of Nitrobenzene Studied by Picosecond Time-Resolved Transient Grating Method

“…Nitrobenzene (NB) is one of the most fundamental molecules and it possesses a variety of unique optical properties. For example, NB is one of the well-known optical Kerr media and used as the standard substance for new nonlinear optical spectroscopies. − NB is frequently used as an energy acceptor, such as an excited state or fluorescence quencher, − and as an optical heat source in photoacoustic and photothermal spectroscopies. − Furthermore, derivatives of NB and nitro substituted aromatic hydrocarbons have attracted the interest many scientists because of their unique properties such as the prominent charge transfer phenomena. − In spite of the fundamental importance of the photophysical characters of NB, the photophysical properties, dynamics, and nature of the excited states of NB have not been well understood. In 1970, Khalil et al reported phosphorescence at low temperature with a lifetime 0.1−1 s, which suggested that the lowest excited triplet (T 1 ) state is of 3 ππ* character.…”

Atomic-Level Molecular Modeling of AOT Reverse Micelles. 1. The AOT Molecule in Water and Carbon Tetrachloride

“…The advantages of AOT are that it forms normal as well as reverse micelles and that its typical aggregation number is conveniently low from a computational point of view (10−60, depending on the solvent and possible other components present). The choice of carbon tetrachloride as the solvent was prompted by its symmetry, by our previous experience of its favorable optical properties in thermal lens and laser E-jump studies of reverse micelles, and by the small number of atoms in the molecule. The relatively moderate size of the aggregates and solvent molecules allows atomic-level modeling instead of the use of lower level approximations for the description of the surfactant molecule. − The results of a series of such theoretical calculations are presented, and estimates for the aggregation number and diameter of AOT/CCl 4 reverse micelles are compared with experimental findings.…”