Temperature-dependent Vibrational Spectroscopic and X-ray Diffraction Investigation of Nanosized Nickel Chromite
2015
Abstrakt
The nanocrystalline nickel chromite (NiCr2O4) with particle size of ~ 20 nm was prepared by auto-combustion method. The nanocrystals were characterised by powder X-ray diffraction, vibrational spectroscopy and magnetic measurements.
The expected structural phase transitions (cubic - tetragonal - orthorhombic) were studied by methods of temperature-dependent X-ray powder diffraction and vibrational spectroscopy. The evolution of the Raman spectra and X-ray diffraction patterns collected from 350 K down to 4 K confirmed the cubic-to-tetragonal distortion at ~ 250 K, whereas the tetragonal-to-orthorhombic transition was not confirmed in the nanocrystalline sample.