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G Sawatzky

Publications and source records attributed to G Sawatzky.

4 recordsLinked to original sources

Thermoelectric power of HoBaCo2O5.5: possible evidence of the spin blockade in cobaltites.

Thermoelectric power measurements have been performed for an ordered oxygen-deficient perovskite, HoBaCo2O5.5, in which the alternative layers of CoO6 octahedra and of [CoO(5)](2) bipyramids are occupied by Co3+ species. The T-dependent Seebeck coefficient S shows a clear change of the conduction regime at the metal-insulator (MI) transition (T(MI) approximately 285 K). The sign change of S from S<0 to S>0 can be explained assuming that a spin state transition occurs at T(MI). In the metallic state, Co2+ e(g) electrons are moving in a broad band on the background of high or intermediate spin Co3+ species. In contrast, the insulating behavior may result from the Co3+ spin state transition to a low-spin Co3+ occurring in the octahedra. In this phase the transport would occur by hopping of the low-spin Co(4+)t(2g) holes, whereas the high-spin Co2+ electrons become immobilized due to a spin blockade.

Journal Article↗

Soft x-ray resonant diffraction study of magnetic and orbital correlations in a manganite near half doping.

We have utilized resonant x-ray diffraction at the Mn L(II,III) edges in order to directly compare magnetic and orbital correlations in Pr0.6Ca0.4MnO3. Comparing the widths of the magnetic and orbital diffraction peaks, we find that the magnetic correlation length exceeds that of the orbital order by nearly a factor of 2. Furthermore, we observe a large (approximately 3 eV) spectral weight shift between the magnetic and orbital resonant line shapes, which cannot be explained within the classic Goodenough picture of a charge-ordered ground state. To explain the shift, we calculate the orbital and magnetic resonant diffraction line shapes based on a relaxed charge-ordered model.

Journal Article↗

Defining scholarly activity in nursing education.

In an attempt to address the question of what activities should be considered scholarly, thereby warranting their inclusion in a nursing faculty evaluation model, a study was undertaken which surveyed all National League for Nursing accredited baccalaureate educational programs. The items in the instrument were generated utilizing the Delphi method and a pilot study established inter-respondent reliability. A response rate of 73% was attained. Scholarly activity was considered highly important in evaluation for promotion and tenure in over 50% of the schools. There were distinct differences in the activities deemed scholarly when respondents were broken down into categories such as size and type of institution and the existence or non-existence of graduate nursing programs in the same institution.

Colorado↗

Low frequency cauterization.

Low frequency cauterization is presented in comparison to the related high frequency method. Both methods are defined and compared and their advantages and disadvantages are illustrated. Finally, a promising combination of both methods is described.

Electrocoagulation↗