Neutron diffraction from small numbers of Langmuir-Blodgett monolayers of manganese stearate

We report the observation of neutron diffraction from as few as three monolayers of manganese stearate on a plate of about 4-${\mathrm{cm}}^2$ area. These room-temperature (paramagnetic state) measurements could be adequately calculated on a laminar model of the crystal structure. Similar calculations, extended to a hypothetical magnetically ordered structure, indicate that the interlayer magnetic structure would be observable already with three layers of magnetic unit cells.