Experimental determination of the dipolar field in Mn12-acetate

TL;DR

This study directly measures the dipolar magnetic field in Mn12-acetate crystals, revealing a value consistent with theoretical predictions, by exploiting the properties of minor species with lower anisotropy barriers.

Contribution

It provides the first direct experimental determination of the dipolar field in Mn12-acetate, using the low coercive fields of minor species.

Findings

Dipolar field in Mn12-acetate is 51.5 ± 8.5 mT.

Results align with theoretical models.

Minor species facilitate the measurement.

Abstract

Crystals of the molecular magnet Mn12-acetate are known to contain a small fraction of low- symmetry (minor) species with a small anisotropy barrier against spin reversal. The lower barrier leads to faster magnetic relaxation and lower coercive field. We exploit the low coercive fields of the minor species to make a direct determination of the dipole field in Mn12-ac. We find that the dipolar field of a fully magnetized crystal is 51.5 \pm 8.5 mT, consistent with theoretical expectations.