High-field magnetization process in the S=1/2 chain [PM·Cu(NO3)2·(H2O)2]n (PM=pyrimidine)

We report the magnetization process on the S=1/2 antiferromagnetic Heisenberg chain [PM·Cu(NO3)2·(H2O)2]n (PM=pyrimidine). It has become clear that the staggered magnetic field plays an important role in the magnetic behavior from magnetic susceptibility and specific heat studies on single-crystalline samples. The magnetization curve for a single crystal of [PM·Cu(NO3)2·(H2O)2]n does not show a divergent slope, but rounding behavior at the saturation field due to the effect of the staggered magnetic field even at 100 mK. [Copyright &y& Elsevier]