Low temperature static magnetization of an organic ferromagnet, β-p-NPNN

A 3He refrigerator mountable to a commercial SQUID magnetometer has been developed, which enables us to measure static magnetizations of a sample at temperatures below 2 K conveniently. The design and usage of the system are outlined. We have applied this to study static magnetic properties of an organic ferromagnet, β-p-NPNN, and have confirmed that the saturation magnetization is 1 μB per molecule. No hysteretic behavior has been detected, when the field was applied along the easy axis. This indicates that β-p-NPNN is a very soft magnet, as expected for an isotropic Heisenberg magnet based on organic radicals.

Graphical abstractA 3He refrigerator mountable to a commercial SQUID magnetometer has been used to measure static magnetizations of the first organic ferromagnet, β-p-NPNN. The study has revealed that its saturation magnetization is exactly 1 μB per molecule unlike the previous study with a dynamical method.Figure optionsDownload full-size imageDownload as PowerPoint slide