MAGNETIZATION AND DYNAMICS OF REENTRANT FERRIMAGNETIC SPIN-GLASS [MNTPP]( /+)[TCNE](CENTER-DOT-)CENTER-DOT-2PHME/

We present direct current (dc) magnetization M(T,H) and alternating cu rrent (ac) susceptibility chi(ac)(T,H,f) data for the quasi-one-dimens ional molecule-based ferrimagnet [MnTPP](::+)[TCNE](.-). 2PhMe traphen ylporphyrinato,(.)TCNE=tetracyanoethylene). Static scaling of the real part chi' of the ac susceptibility and data collapse of M(T,H) over a limited reduced temperature range above T-c approximate to 13 K lead to the critical exponents gamma approximate to 1.6, beta approximate t o 0.5, and delta approximate to 4.2. Below T-c, chi(ac) depends sensit ively on frequency and exhibits a striking double-peak structure simil ar to that found in reentrant spin glasses. Possible models for the fr equency dependence of the peaks observed in chi(ac) are discussed. (C) 1996 American Institute re of Physics.