Experimental investigation of low dimensional spin system in metal oxides

Abstract

Nano particles of SrCrO4 were manufactured by sol-gel technique. The crystal part of
SrCrO4 is monoclinic having space group P21/n. We calcined it at 950°C temperature. Its c
and a lattice parameter are 6.77 and 7.08 which is very close to the reported ones. Ba and Cadoped SrCrO4 were also synthesized by sol-gel method by various concentrations for x= 0.2,
0.4, 0.6 and 0.8. Doping samples also sintered at 950°C for 2 hours in order to obtain fine
powder. Different characterization techniques such as XRD, Ultra-violet-Spectroscopy, PL
Spectroscopy and FTIR Spectroscopy were used to analyze SrCrO4, Ba and Ca-doped
SrCrO4. XRD tells us about the crystal size and dislocation density of samples. The value of
2? for the XRD patterns is ranging from 5 to 95. Four peaks are observed in the UV-spectra
of SrCrO4 which occur at 350nm, 380nm, 700nm and 750nm. The UV band gap of SrCrO4
is 3.25 eV. In PL spectra, two peaks are observed one at 480nm and other at 410nm. At
480nm, the energy of emitted photons is 2.5eV, while at 410nm the emitted photons has
energy of 3ev. In the FTIR analysis, the core modes frequently showed by CrO4 unit are
symmetric stretching bond (?1 (A1)), symmetric bending mode (?2 (E)), asymmetric
stretching mode (?3 (F2)) and asymmetric bending mode (?4 (F2)).