We have carried out magnetic measurements on the layered magnets Ni-2(OH)(3
)(N(CN)(2)) (NiAM), Co-5 (OH)(8)(N(CN)(2))(2). 6H(2)O (CoAM), Co-5(OH)(8) (
C12H25SO4)(2). 2NH(3) (CoDOS), and Co-5 (OH)(8) (C7H15CO2)(2). 4H(2)O ( CoC
AP), using various experimental methods, including muon spin relaxation (mu
SR). We find phase transitions at temperatures T-M in all the samples, cha
racterized by a change in the magnetic susceptibilty and loss of initial mu
on spin polarization.