Israeli researchers alter magnetic properties of minerals - study

The technique was developed by a team from the Technion-Israel Institute of Technology.

Scanning electron microscope images of manganese carbonate crystals, without (a) amino acids and with (b) amino acids incorporated in the crystal. Scale bar: 200 nanometers. (photo credit: TECHNION-ISRAEL INSTITUTE OF TECHNOLOGY)
Scanning electron microscope images of manganese carbonate crystals, without (a) amino acids and with (b) amino acids incorporated in the crystal. Scale bar: 200 nanometers.
(photo credit: TECHNION-ISRAEL INSTITUTE OF TECHNOLOGY)

Israeli researchers created a method for controlling the magnetic properties of materials inspired by natural mineral growth processes by organisms, the Technion-Israel Institute of Technology announced on Thursday.

The technique was developed by a team led by Prof. Boaz Pokroy and doctoral student Arad Lang of the Technion Department of Materials Science and Engineering, Dr. Elad Caspi and other researchers from the Nuclear Research Institute in the Negev and Drs. Giorgia Confalonieri and Catherine Dejoie of the European Synchrotron Radiation Facility in Grenoble, France.

Biominerals are structures created by nearly all animals for various purposes, including bones in vertebrates and a mollusk's protective shell.

Such structures bear mechanical properties and are difficult to break, in part due to the fact that within the mineral structure, organic minerals hold the mineral together and prevent cracks from developing.

Based on this process, a team led by Pokroy synthesized manganese carbonate crystals in the presence of amino acids. In this process, the amino acids incorporate themselves into the crystal structure of the mineral. The molecules force the manganese and carbonate ions to split and distort the structure of the crystal.

Prof. Boaz Pokroy (credit: TECHNION-ISRAEL INSTITUTE OF TECHNOLOGY)Prof. Boaz Pokroy (credit: TECHNION-ISRAEL INSTITUTE OF TECHNOLOGY)

Magnetic properties of the new material

After this, the team measured the magnetic properties of the crystals and found that the manganese carbonate containing the amino acids had a higher magnetic susceptibility than the original material, meaning it is easily affected by external magnetic fields. Furthermore, the researchers found that the reactiveness to magnetism increased and the threshold temperature—the maximum temperature at which the material reacts to magnetism—increased as more amino acids were added.

These phenomena are a result of the distance increasing between the atoms within the crystal. As this weakens the magnetic interactions within the crystal, external magnetic fields have a stronger effect.

Arad Lang (credit: TECHNION-ISRAEL INSTITUTE OF TECHNOLOGY)Arad Lang (credit: TECHNION-ISRAEL INSTITUTE OF TECHNOLOGY)

This study shows the feasibility of altering the magnetic properties of materials by incorporating organic molecules that are not magnetic and sheds light on the potential applications in fields such as microelectronics and medicine.