LOW-TEMPERATURE ADIABATIC STUDIES OF SPIN-FLOP STATES IN ANTIFERROMAGNETS

The theoretical basis for adiabatic investigations of antiferromagnetic spin-flop states is given. Experimental details of such experiments are briefly described and results of such experiments on CoCl26H2O and MnCl24H2O, which have known spin-flop states, are given. Results are also presented indicating that the two antiferromagnetic substances CoBr26H2O and FeCl24H2O exhibit spin flopping in accessible experimental regions. CoBr26H2O has a critical field of the order of 7500 G in the region 1.15°K to its triple point, 2.91°K. FeCl24H2O apparently exhibits spin flop below 0.68°K above a field equal to about 5500 G. The method also shows the lack of spin flopping in MnBr24H2O below 10 000 G above 1°K. © 1969 The American Physical Society.