dc.contributor.author |
Vanitha, P V
|
|
dc.contributor.author |
Nagarajan, R
|
|
dc.contributor.author |
Rao, C N R
|
|
dc.date.accessioned |
2012-11-23T10:34:23Z |
|
dc.date.available |
2012-11-23T10:34:23Z |
|
dc.date.issued |
2003-08 |
|
dc.identifier |
0022-4596 |
en_US |
dc.identifier.citation |
Journal of Solid State Chemistry 174(1), 74-79 (2003) |
en_US |
dc.identifier.uri |
https://libjncir.jncasr.ac.in/xmlui/10572/1058 |
|
dc.description |
Restricted Access |
en_US |
dc.description.abstract |
Mössbauer studies of 2% 57Fe-doped Nd0.5Ca0.5MnO3 and Nd0.5Sr0.5MnO3 have been carried out over the 4.2–300 K range after ensuring that such doping does not change their basic properties. The charge-ordering transition in these manganates is marked by abrupt changes in the quadrupole splitting. In the case of Nd0.5Ca0.5MnO3, two phases manifest themselves on cooling below the charge-ordering transition temperature. The evolution of the spectra as a function of temperature shows that long-range magnetic order does not occur sharply. The observed evolution with temperature is different in the two materials studied. In Nd0.5Ca0.5Mn0.9857Fe0.02O3, it resembles that of a disordered magnetic material, whereas the temperature dependence of line shape of Nd0.5Sr0.5Mn0.9857Fe0.02O3 is typical of a superparamagnetically relaxed magnetic system. Although both the manganates show well-resolved magnetic hyperfine spectra at 4.2 K, the lines are slightly broad indicating possible coexistence of phases at low temperatures. A weak paramagnetic signal is also seen in the spectra of both the manganates at 4.2 K. |
en_US |
dc.description.uri |
http://dx.doi.org/10.1016/S0022-4596(03)00177-4 |
en_US |
dc.language.iso |
en |
en_US |
dc.publisher |
Academic Press Inc Elsevier Science |
en_US |
dc.rights |
© 2003 Elsevier Science |
en_US |
dc.subject |
rare-earth manganates |
en_US |
dc.subject |
charge ordering |
en_US |
dc.subject |
magnetic disorder |
en_US |
dc.subject |
superparamagnetism |
en_US |
dc.subject |
Fe-57 Mossbauer spectroscopy |
en_US |
dc.subject |
phase separation |
en_US |
dc.title |
A 57Fe Mossbauer study of charge ordering and phase separation in the rare-earth manganates, Nd0.5Ca0.5MnO3 and Nd0.5Sr0.5MnO3 |
en_US |
dc.type |
Article |
en_US |