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A study is conducted on a 160-nm-thick (Hg0.9Re0.1)Ba2CaCu2Oy [(Hg,Re0-1212] epitaxial thin films that were fabricated on 2degree-18.4degree -tilt SrTiO3 vicinal substrates with thin buffer layers. The studies indicate that the vicinal films had superior crystallinity and superconducting properties comparable to those for conventional films with no tilt.

A study was conducted to understand the strong negative thermal expansion (NTE) exhibited by scandium trifluoride at low temperature, which maintains a cubic Re[O.sub.3] type structure down to at least 10K. Sc[F.sub.3] is found to be the first material with structure similar to Re[O.sub.3] which provide a clear experimental explanation for the observed NTE mechanism.

The theoretical exploration of the high pressure phases of the ionic salt BaRe[H.sub.9] was carried out motivated by the potential high-temperature superconductivity of 'chemically precompressed' hydrogen-rich compounds. The results provide insight into the structural changes in BaRe[H.sub.9] associated with remarkable lowering of metallization pressure the and the expected metallic turn in BaRe[H.sub.9] at the onset of the [H.sub.2]-containing phase.

Micro-Raman spectroscopy and x-ray diffraction techniques were used to compare and characterize rhenium oxide thin films obtained by thermal evaporation of Re[O.sub.3] powders on different substrates, maintained at different temperatures and by reactive magnetron sputtering of a Re metallic target. The electrical and electro-optical behaviors of Re[O.sub.3] films deposited on standard indium tin oxide/glass substrate tested inside asymmetric nematic liquid crystal cells showed an ability to rectify their electro-optical response similar to tungsten trioxide.

Time-of-flight neutron powder diffraction and specific heat measurements were employed to study the nature of thermal expansion in rhenium trioxide, an electrically conducting oxide with cubic symmetry. The temperature evolution of the lattice parameters indicated that Re[O.sub.3] could exhibit negative thermal expansion below room temperature and that the transition from negative to positive thermal expansion depended on sample preparation.

A new mechanism is described for the conversion of Re azide complexes to the corresponding Re imido complexes by [N.sub.2] loss. The results have shown that the oxo rhenium complex has reacted with Ph[N.sub.3] through rhenium azide intermediates to produce the cis [beta] oxo-imido complex, where cis [beta]-I is both kinetically and thermodynamically favored over cis [beta]-II.

The article presents the synthesis, reactivity and the various properties of several N-fused porphyrin rhenium(I) tricarbonyl complexes. These complexes are found to be highly stable against heat, light acids, bases and oxidants.

Weakly bonded rigid heavy clusters (WBRHCs) are used for studying the thermoelectric properties of quaternary icosahedral AlPdReFe quasicrystals obtained by replacing Re with Fe in icosahedral AlPdRe quasicrystals. The results have shown that Fe substitution is more favorable than Ru substitution for the Re site in i-AlPdRe.

DC magnetron sputtering is used for preparing RE-Fe-B films on a Ta buffer layer on thermally oxidized Si substrates. The results have indicated that the film has a high perpendicular coercivity and large magnetic energy product.

A new and potentially useful method of chirality transfer from a coordinated ligand to a metal, consisting of a kinetically controlled diastereoselective proton transfer is presented. The diastereomeric methyl rhenium complex is synthesized and treated at 178 degree Celsius with half an equivalent of methanesulfonic acid in order to test this new method.

The derivatives of aromatic heterocycles represented in the deprotonated forms of rhenium carbene complexes are examined and their intrinsic rate constants are studied. It is found that an increase in aromaticity leads to an increase in the intrinsic rate constant.

The composition dependence of the Seebeck coefficient and the electrical conductivity of AlPdRe icosahedral alloys are presented. It is noticed that the Seeback coefficient rapidly increases with increasing Re or Pd concentration.

The effect of vortex generators on the heat transfer from internally ribbed passages is studied experimentally using a mass transfer technique. The heat/mass transfer from the ribbed surfaces depends on the Re and s/e values.