Structural, Magnetic and Dielectric Studies on Strontium Substituted Nd2CuO4 System

Venugopalan Anbarasu, Appasamy Manigandan, Kandasamy Sivakumar
DOI: 10.4236/jmp.2010.12014                

Abstract

The substitution of Strontium on T'–structured Nd2CuO4 system has been carried out through solid state reaction tech-nique. From the Powder XRD patterns, it is found that the compounds are formed in single phase and crystallizes in orthorhombic structure. The variation in lattice parameters with decreasing nature of volume of the prepared com-pounds confirms the incorporation of lower atomic radii Strontium in Neodymium site. Surface morphology and ele-mental composition studies are also carried out to know the nature of the compounds and effect of Strontium substitu-tion in Nd2CuO4 system. The paramagnetic nature of all the prepared compounds has been identified through magnetization studies and the results are correlated with the electron spin resonance studies by the way of variation in resonance field and broad peak width. Increasing order of dielectric constant on higher doping concentration of Strontium and the least value of dielectric loss at higher frequencies confirms the improved surface transport properties of the prepared compounds.

Keywords

Ln2CuO4, Structural Analysis, Powder XRD, Dielectric Studies, Magnetization, ESR Analysis

Conflicts of Interest

The authors declare no conflicts of interest.

References

[1]	Y. Tokura, H. Takagi and S. Uchida,“A Superconducting Copper Oxide Compound with Electrons as the Charge Carriers,” Nature, Vol. 337, 1989, pp. 345-347.
[2]	H. Takagi, S. Uchida and Y. Tokura, “Superconductivity Produced by Electron Doping in CuO2-Layered Com- Pounds,” Physical Review Letters, Vol. 62, No. 10, 1989, pp. 1197-1200.
[3]	H. Muller-Buschbaum and W. Z. Wollschlager, “Über Ternäre Oxocuprate. VII. Zur Kristallstruktur von Nd2CuO4,” Zeitschrift für Anorganische und Allgemeine Chemie, Vol. 414, 1975, pp. 76-80.
[4]	H. Muller-Buschbaum and W.Z. Wollschlager, “Über Oxocuprate. XV Zur Kristallstruktur von Seltenerd Metal Oxocupraten: La2CuO4, Gd2CuO4,” Zeitschrift für Anor- ganische und Allgemeine Chemie, Vol. 428, 1975, pp. 120- 124.
[5]	T. V. Ramakrishnan and C. N. R. Rao, “Superconductivity Today–An Elementary Introduction,” 2nd Edition, Uni- versites Press (India), Hyderabad, 1999, pp. 26-54.
[6]	G. H. Kwei, S. W. Cheong, Z. Fisk, F. H. Garzon, J. A. Goldstone and J. D. Thompson, “Structure and Oxygen Stoichiometry for the Electron-Doped Cuprate Supercon- ductor Nd1.85Ce0.15CuO4-d,” Physical Review B, Vol. 40, 1989, pp. 9370-9373.
[7]	X. Zhang, C. R. A. Catlow, S. C. Parker and A. Wall, “Simulation Study of Pressure-Induced Structural Changes in La2CuO4 and in La1.83Sr0.17CuO4,” Journal of Physics and Chemistry of Solids, Vol. 53, No. 6, 1992, pp. 761-770.
[8]	E. F. Paulus, I. Yehia, H. Fuess, J. Rodriguez, T. Vogt, J. Ströbel, M. Klauda and G. Saemann-Ischenko, “Crystal Structure Refinement of Nd2−xCexCuOrm4 (x = 0.05−0.30) by X-Ray (295 K) and Neutron (1.5 K) Powder Diffrac- tion,” Solid State Communications, Vol. 73, No. 11, 1990, pp. 791-795.
[9]	J. F. Raber, “Experimental Methods in Polymer Chemis- try–Physical Principal and Applications,” John Wiley, New York, 1980, pp. 332-352.
[10]	V. B. Zlokazov, “AUTOX–A Program for Autoindexing Reflections from Multiphase Polycrystals,” Computer Phy- sics Communications, Vol. 85, No. 3, 1995, pp. 415-422.
[11]	O. D. Jayakumar, I. K. Gopalakrishnan and S. K. Kulsh- reshtha, “The Structural and Magnetization Studies of Co-Doped ZnO Co-Doped with Cu: Synthesized by Co- Precipitation Method,” Journal of Materials Chemistry, Vol. 15, No. 34, 2005, pp. 3514-3518.
[12]	O. D. Jayakumar, I. K Gopalakrishnan, and S. K. Kulsh- reshtha, “On the Room Temperature Ferromagnetism of Mn Doped ZnO,” Physica B, Vol. 381, No. 1-2, 2006, pp. 194-198.
[13]	H. Samata, T. Komiyama, S. Tsuboi, Y. Nagata, T. Uchid, M. Ohtsuk and M. Der Lan, “Electrochemical Crystal Growth of Superconducting Cuprates,” Journal of Physics and Chemistry of Solids, Vol. 58, No. 10, 1997, pp. 1547- 1552.
[14]	J. A. Olarte, L. C. Moreno and A. Mariño, “Suscep- tibility and EPR Studies of LaMnx-1CoxO3 Synthesized by Citrate Precursor Method,” Microelectronics Journal, Vol. 39, No. 11, 2008, pp. 1245-1247.
[15]	S. Angappane, M. Pattabiraman, G. Rangarajan, K. Sethupathi, B. Varghese and V. S. Sastry, “ESR Study of Spin–Lattice Correlated Clusters in Single Crystalline Nd0.7Sr0.3MnO3,” Journal of Physics: Condensed Matter, Vol. 19, 2007, pp. (036207)1-16.