Introduction
Gadolinium (atomic number 64) is a Heavy Rare Earth Element that sits right in the middle of the lanthanide series. It is famous for having unusual magnetic properties and is crucial for modern medical diagnostics.
Chemical & Physical Properties
A silvery-white, malleable, and ductile metal. Gadolinium is unique because at room temperature, it is paramagnetic, but it becomes ferromagnetic (strongly magnetic like iron) when cooled to just below room temperature (around 20°C or 68°F). It also has the highest thermal neutron capture cross-section of any stable element.
Occurrence & Production
Found in many minerals, including monazite and bastnäsite, often associated with other heavy rare earths.
Key Applications & Uses
- MRI Contrast Agents: This is its most famous use. Because of its varied magnetic properties, gadolinium compounds are injected into the body to enhance tissue contrast in Magnetic Resonance Imaging (MRI) scans, helping doctors detect tumors and lesions.
- Magnetic Refrigeration: Due to its significant magnetocaloric effect (heating up when magnetized and cooling down when demagnetized), it is being researched for efficient, gas-free magnetic refrigeration systems.
- Nuclear Marine Propulsion: Used as burnable poison in the fuel of nuclear reactors, particularly in naval propulsion systems.
Future Outlook & Significance
Gadolinium is vital to the healthcare industry. Its potential role in future green refrigeration technologies could also significantly increase its demand.