ISSN:
0741-0581
Schlagwort(e):
Electron energy loss spectroscopy
;
Varying O2 content
;
Crystallographic orientation dependence of oxygen near edge features
;
Life and Medical Sciences
;
Cell & Developmental Biology
Quelle:
Wiley InterScience Backfile Collection 1832-2000
Thema:
Allgemeine Naturwissenschaft
Notizen:
The high Tc superconducting material YBa2Cu3O7 shows a complex relationship between microstructure and oxygen content, which are controlled by length of heat treatment, atmosphere, and quench rate. An AEM investigation studying changes in the oxygen near edge features was undertaken. Electron energy loss spectroscopy (EELS) measurements have the important advantage that they can be made on single crystal grains, allowing orentation-dependent studies. Both ion-milled and crushed samples with varying O2 content were analyzed. The structure of YBaCu3O7 was determined by neutron diffraction to be orthorhombic with distinct Cu-O chains along the b-axis as well as Cu-O planes in the a - b plane. Therefore, by looking for a crystallographic dependence of the oxygen K-edge one might be able to distinguish inequivalent oxygen atoms by their core level binding energy and correlate site occupancy with varying O2 content. The EELS results on the oxygen K-edge are strongly dependent on oxygen content, most noticeably when the c-axis is parallel to the electron beam.
Zusätzliches Material:
3 Ill.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1002/jemt.1060080309
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