LATTICE AND STRUCTURAL DISTORTIONS IN Gd3+ SUBSTITUTED LaMnO3: INFRARED REFLECTIVITY MEASUREMENTS

被引：0

作者：

Ahmad, J. ^{[1
]}

Zakia, G. ^{[1
]}

Abbas, H. ^{[1
]}

Bukhari, S. H. ^{[2
]}

Nissar, U. ^{[1
]}

Jamil, M. T. ^{[1
]}

Khan, J. A. ^{[1
]}

Ahmad, U. ^{[1
]}

Ali, S. A. ^{[1
]}

Sultan, T. ^{[3
]}

机构：

[1] Bahauddin Zakariya Univ, Dept Phys, Multan 60800, Pakistan

[2] GC Univ Faisalabad, Dept Phys, Layyah Campus, Layyah 31200, Pakistan

[3] UCET, Dept Civil Engn, Bzu Multan 60800, Pakistan

来源：

JOURNAL OF OVONIC RESEARCH | 2019年 / 15卷 / 05期

关键词：

Sol Gel combustion synthesis; FTIR spectroscopy; Infrared reflectivity; Effective charges; EFFECTIVE CHARGES; MANGANITES; GDMNO3;

D O I：

暂无

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

Polycrystalline La1-xGdxMnO3 multiferroics (x = 0.0, 0.2, 0.4, 0.6, 0.8 and 1.0) have been successfully synthesized by sol-gel combustion method. Rietveld refinement of X-ray diffraction (XRD) patterns clearly demonstrates a structural distortion from orthorhombic to rhombohedral perovskite-type structure, which suggests strong Jahn-Teller distortion. The infrared reflectivity (IR) spectra are measured at room temperature over a frequency range 30-7500 cm(-1) by Fourier transform infrared (FTIR) spectrometer which exhibits several optical phonons. The resonant frequency (omega(TO(j))), oscillator strength (S-j) and damping factor (gamma(j)) of various observed optical phonons have been determined by fitting the Lorentz oscillator model to the measured reflectivity spectra. The iii Too) is found dependent on Gd concentration suggesting a strong electron-phonons interaction in the system. The optical conductivity sigma(1) (omega) calculated by using the Kramers-Kroning analysis of the IR spectra also confirms the phase transition on increasing the Gd concentration. The Born effective charges have been calculated using the transverse (TO) and longitudinal optical (LO) modes to understand the role of ionic polarization in the present multiferroic system.

引用

页码：345 / 355

页数：11

共 41 条

[1] Silica-coated gadolinium-doped lanthanum strontium manganite nanoparticles for self-controlled hyperthermia applications [J].