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Photon statistics of blinking CdSe-ZnS nanocrystals interacting with a continuous wave laser field is analyzed showing that the process is described by a ballistic Levy walk. It is shown that Mandels Q parameter, describing the fluctuations of the photon counts is increasing with time eve in the limit of long time.

The alloy nanowires of [Zn.sub.x][Cd.sub.1-x]Se with composition x=0,0.2,0.5,0.7 and 1 were successfully synthesized by a chemical vapor deposition (CVD) method assisted with laser ablation. The [Zn.sub.x][Cd.sub.1-x]Se nanowires were found to be single crystalline and can serve as important integrated full-color display elements in optical and sensory nanotechnological applications.

The overall rate coefficients of the reactions of CSe(sub 2), SCSe, and OCSe with O((super 3)P) atom are examined. An excellent match between the decay rate of OCSe with the appearance rate of CO upon O atom reactions is found, which suggest that only a single channel is open while the measured rate coefficient may be used to describe the single reaction, O + OCSe -> CO +SeO.

Charging effects in a CdSe nanotetrapod are theoretically investigated by using an atomistic pseudopotential method. It is found that surface polarization can significantly change the electron wave functions and depending on the situation the tetrapod can behave like a single coherent dot to weakly coupled multiple dots.

The evidence for an interaction between the quantum dot exciton fine structure states F= plusmn1 is obtained by measuring the dynamics of transition among those states, exciton spin relaxation or flipping. The results for colloidal Cdse quantum dots revealed strong size dependence for the exciton spin relaxation, consistent with its origin being attributed to a long-range contribution to the electron-hole exchange interaction.

A comprehensive study was performed on the polar (0001) and (0001) and nonpolar (1120) wurtzite CdSe surfaces that are exposed during crystal growth using first-principles density functional theory calculations. Stabilization of these surfaces by relaxation and reconstruction was considered.

An electron microscopic observation of crystal shape development when PbSe nanocrystals were synthesized using a dynamic injection technique at different temperatures in the presence of oleic acid is presented. A two-step evolution mechanism is proposed, indicating that the shape evolution of PbSe nanocrystals is dependent on the growth time, whereas the crystalline size can be tuned by varying the growth temperature under the studied conditions.

Optically active seleninate esters are obtained by chromatographic resolution on an optically active column. The reaction of the optically active seleninate ester and the sulfinate ester having bulky substituents with Grignard reagents is found to proceed with the retention of stereochemistry to give an optically active selenoxide and sulfoxides, respectively.