Department of Energy Argonne National Laboratory Office of Science NEWTON's Homepage NEWTON's Homepage
NEWTON, Ask A Scientist!
NEWTON Home Page NEWTON Teachers Visit Our Archives Ask A Question How To Ask A Question Question of the Week Our Expert Scientists Volunteer at NEWTON! Frequently Asked Questions Referencing NEWTON About NEWTON About Ask A Scientist Education At Argonne Rare Earth Magnets
Name: Bobby O.
Status: other
Age: 50s
Location: N/A
Country: N/A
Date: 2001-2002


Question:
What exactly are rare-earth magnets and how are they formed?


Replies:
Rare earths are the 14 elements in the periodic table that start with the element Lanthanum and end with the element Luthecium. The rare earth elements are magnetic because their 4f shells are not full. The elements as one moves to the right in the periodic table fill one electron at a time. The 4f shells each can have two spin states, up or down. Because it is more energetically favorable, Hunds Rule, the 1st 7 electrons fill with their spins all up. Spin state for Eu is around 7 times 1/2 (from each electron).

Rare earth magnets are made from rare-earth elements. Typically these are compounds or composites with Fe.

Dr. Harold Myron


The rare earths, also called the "lanthanides" have unpaired electrons in their "f" orbitals.

Various compounds of these elements are used to produce very strong magnets. The particular compounds depends upon both chemical, engineering, and economic considerations. Search the term: "rare earth magnets" on the Internet and I think you will find a wealth of info -- probably more than you want to know.

Vince Calder



Click here to return to the Physics Archives

NEWTON is an electronic community for Science, Math, and Computer Science K-12 Educators, sponsored and operated by Argonne National Laboratory's Educational Programs, Andrew Skipor, Ph.D., Head of Educational Programs.

For assistance with NEWTON contact a System Operator (help@newton.dep.anl.gov), or at Argonne's Educational Programs

NEWTON AND ASK A SCIENTIST
Educational Programs
Building 360
9700 S. Cass Ave.
Argonne, Illinois
60439-4845, USA
Update: June 2012
Weclome To Newton

Argonne National Laboratory