Magnetic and Electric Studies of a New Cu(II) Perovskite-like Material

Abstract

Thermal analysis of a lipid-like bilayer of [(CH2)9 (NH3)2]CuCl4 indicates one minor transition at 303 K and the following five major ones (with entropies in J/K-mole): Phase T5=188K/ΔS5=5.43 Phase T 4=228K/ΔS4=1.90 Phase T 3=288K/ΔS3=4.06 Phase T 2=346K/ΔS2=0.36 Phase T 1=383K/ΔS1=3.80 Phase. (VI) (V) (IV) (III) (II) (I) The initial magnetic susceptibility at 320 Hz and a magnetic field of 160 A/m in the temperature range 75 - 290 K revealed a Curie-Weiss behavior of phase (V) and possible ferromagnetic ordering of phases (VI) and (IV) at low temperatures. The variation of the dielectric permittivity with temperature at 60.0 Hz - 100 kHz indicates large changes of the dipole moment at the transition temperatures. The conductivity is thermally activated and frequency dependent, following the universal power law: σ(ω) = σ dc + A(T)ωs(T). Values of s being phase dependent. For phase (I), T > 383 K, band type conduction prevails. Hopping conduction is found in phases(II) and (III). Comparison with other Cu-and Cd-containing materials is made.