A new molecular-based ferromagnet [Cu(en)]~3[Fe(CN)~6]~2.3H~2O has been synthesized and characterized. Variable-temperature magnetic susceptibility, zero-field-cooled magnetization (ZFCM), field-cooled- magnetization (FCM) and the hysteresis loop measurements show that a ferromagnetic interaction exists between the copper(II) and iron (III) ions. The critical phase-transition temperature, coercive force and remnant magnetization are 11.0K, 20×10^-^4T, and 1.70× 10^-^1cm^3. mol^-^1.T respectively. To our knowledge, the present complex is the first example with a Tc value for the hybrid type copper(II)-iron(III) complexes.

Key words: COPPER COMPLEX, IRON COMPLEX, MAGNETISM, CYANIDES, ETHANEDIAMINE P, MAGNETIZATION, MAGNETIC FIELDS