Crystallographic and Magnetic Properties of KFeO$_2$

The crystallographic and magnetic properties of KFeO
$_2$
powder prepared by ball-mill method, have been studied by X-ray diffraction (XRD), MÖssbauer spectroscopy, and vibrating sample magnetometer (VSM) measurements. The crystal structure of KFeO
$_2$
powder at room temperature is determined to be an orthorhombic structure of Pbca with its lattice constants
$a_0 = 5.594, b_0 =11.247$
, and
$c_0=15.863$
Å by Reitveld refinement. The
$M$
-
$H$
curves show antiferromagnetic behavior at 34 K and room temperature. MÖssbauer spectra of KFeO
$_2$
were taken at various temperatures ranging from 4.2 to 600 K. And the NÉel temperature
$(T_N)$
was determined to be 930 K. The magnetic hyperfine field and isomer shift value at 4.2 K were 519 kOe and 0.19 mm/s, respectively.