  We report on the structural, frequency dependent ac susceptibility, dc
magnetization and magnetoresistance (MR) measurements on polycrystalline
samples of La0.86Ca0.14Mn1-yCryO3(y = 0, 0.1 and 0.2) prepared by sol-gel
technique. For y = 0, a paramagnetic to ferromagnetic transition was observed
at TC = 185 K. For y = 0.1, the value of TC = 200 K, an increase of 15 K and
for y = 0.2, the TC = 195 K, an increase of 10 K. The imaginary part of the ac
susceptibility of all the three samples shows a secondary transition at Tf <
TC. For y = 0, there is no definite law to account for the frequency dependence
of Tf and is attributed to a transition arising out of a canted structure.
However, in the case of y = 0.1 and 0.2, the frequency dependence indicate the
presence of a reentrant spin glass transition at Tf. Though all the three
samples show a semi-conducting behavior between 300 and 5 K, a negative MR was
observed corresponding to TC and Tf. The value of MR decreased for the Cr
substituted samples.
