Formation process, phase analysis and superconducting properties of MoNx thin films prepared by DC and RF reactive magnetron sputtering were Investigated. The optical emission spectra of N2 plasma were measured by a spectroscope. In N2 plasma of DC and RF magnetron sputtering, excited N2 molecules, N2 ions and excited Mo atoms were observed. The Tc of cubic MoNx films prepared by DC and RF modes was found to range between 8.5 K and below 4.2 K. B1 like MoN films were nonsuperconducting above 4.2 K in contrast to theoretical predictions.

Application of electron spin echo Fourier transform EPR (ESE-FT-EPR) to photoinduced chemical reactions is presented. Main purpose of this study is to observe broad EPR spectra of free radicals having very short T~ by means of the ESE-FT-EPR technique. Details of the experimental procedures are described. In ESE experiments design of the resonator is important to obtain sufficient spectral bandwidth because of use of multiple pulses which decreases the bandwidth. We designed and constructed Loop-Gap-Resonators (LGR) for light irradiation experiments and their specifications were examined. The phase cycling method is essential to obtain pure ESE signals and proper time resolution by eliminating unwanted FID signals which result from imperfect pulse angles. We applied this technique to observe the photo-induced electron transfer reaction between tetraphenylporphinato zinc(II) (ZnTPP) and duroquinone (DQ) in an ethanol solution, and successfully observed the time resolved EPR spectra of the both Zn(TPP) cation and DQ anion radicals by ESE-FT-EPR of the Hahn echo. The half-height ¡ of envelope of EPR spectrum of Zn(TPP) § which is never observed in ordinary FT-EPR, is about 16 MHz. Specificity of spectra and the time resolution are compared among the ESE-FT-, FT-and cw-Time-Resolved-EPR (cw-TREPR) techniques.

A Fourier transform (FT) EPR technique has been used to study the photoinduced electron transfer from zinc-substituted myoglobin (ZnMb) to 1,4-benzoquinone (BQ). Both porphyrin cation and BQ anion radicals (BQ~) were observed, which provide direct evidence of an electron transfer occurring between a porphyrin moiety (ZnPP) in myoglobin and BQ. Electron transfer rate constants, spinÈlattice relaxation times of triplet porphyrin and BQ~and magnitudes of chemically induced dynamic electron polarization (CIDEP) due to the triplet mechanism (TM) and the radical pair mechanism (RPM) were evaluated from decay analyses of the FT-EPR signals of BQ~. These results were compared with those for a [5,10,15,20-tetrakis(4-sulfonatophenyl)porphinato]zinc(II) (ZnTPPS)ÈBQ system and discussed in terms of protein e †ects in ZnMb. We concluded that electron transfer occurs from the ZnPP moiety to BQ which is located at the surface of myoglobin.

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