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The ellipsometric properties of Cd(sub 1-x)Mn(sub x)Te/CdTe superlattices (SLs) and of Cd(sub 1-x)Mn(sub x)Te thin films grown by molecular beam epitaxy (MBE) are studied using spectroscopic ellipsometry (SE). It was found that SE is the most suitable technique to monitor the MBE growth, also in situ, of dilute magnetic low-dimensional semiconductor systems.

Sub-Doppler high-resolution excitation spectra of dibenzo-p-dioxin (DD) are observed in experiments. The results indicate that the line widths were much larger than the instrumental resolution, and the lifetime of the S1 state was evaluated to be approximately 500 ps.

The current status of transition metal cluster surface characteristics as influenced by size effects is presented. Determination of metal cluster structures and reactivity of bimetallic clusters are addressed.

The molecular beam epitaxial (MBE) growth of coherent three-dimensional islands is of much interest, due to potential applications in lasers and infrared detectors, based on quantum dots (QDs). The optical properties of self-assembled quantum dots (SAQDs) grown on unpatterned substrates using spatially, spectrally and temporally resolved cathodoluminescence (CL) methods, have been examined. A sample show multiple and distinct emission features within its CL line shape was analyzed. The CL approach can over simultaneous spatial and spectral information.

A finite-element method for the analysis of eigenstates in the valence band of quantum wires with arbitrary potential profiles has been developed, based on the Galerkin procedure. The effects of band mixing are considered and boundary conditions at heterointerfaces are also taken in to account. Numerical examples are given for circular, square, triangular and rectangular quantum wire structures.

Vacuum ultraviolet photoionization mass spectrometry was used to determine the primary photoproducts of the photodissociation in a string of iron cyclopentadienyl compounds. The photolysis of these compounds located in a molecular beam synthesized alkyl radicals and alkene. Indenyl compound 7 was examined to study the effect of ring slippage on alkene development. The indenyl ring replaced the cyclopentadienyl ring, but the quantity of propene and propyl radical was not altered. This proved that ring slippage influences alkene growth.

Surface magnetism is of interest and the link between the magnetic anisotropies and crystal structures is of particular interest. The magnetic properties of Co/Cr films and multilayers have previously been reported. The novel fabrication and structural transformation of metastable hcp Ni(sub80)Fe(sub20) (1100) films grown on Co(1100) and Cr(211) is now reported. The control of the crystal structure and magnetic anisotropy (MA) of such films through the selection of suitable bugger layers and by variations in film thickness, is demonstrated.

The crossed molecular beam method is used for studying the reaction of ground state boron atoms, B([super 2][P.sub.j]), with allene, [H.sub.2]CCC[H.sub.2]([super 1]X[A.sub.1]). The product isomers formed in the reaction of boron atoms are compared with that formed with methylacetylene.

Laser vaporization helps in producing V(C6H6)(sub 1,2) complexes in a molecular beam. Efficient one-photon ionization also occurs for both complexes at this wavelength.