Lanthanides

Lanthanides
User:Double sharp, based on File:Simple Periodic Table Chart-en.svg by User:Offn · CC BY-SA 4.0 · source
Name	Lanthanide series
Atomic number range	57–71
Block	f-block
Appearance	Silvery-white metals
Discovery	19th century

Lanthanides Lanthanides are a group of fifteen metallic chemical elements with atomic numbers 57 to 71, known for their similar chemical behavior and prominent role in modern technology. They feature in research by figures such as Dmitri Mendeleev, Antoine Lavoisier, and institutions like the Royal Society and Max Planck Society due to their placement in the periodic table and influence on materials science. Industrial demand from companies such as Toyota, Siemens, and Nvidia has driven geopolitical interest from nations including China, United States, and Australia.

Introduction

The fifteen elements beginning with the element after Barium and ending before Hafnium occupy the 4f subshell and are often discussed alongside the actinide series in contexts like the Periodic Table of Elements and collections curated by the American Chemical Society and Royal Society of Chemistry. Their study intersects with historical research by scientists such as Jöns Jakob Berzelius and Carl Gustaf Mosander and with modern analytical techniques developed at facilities like CERN and Lawrence Berkeley National Laboratory. Economic discussions involving these elements regularly appear in reports from the World Bank and analyses by the International Energy Agency because of their relevance to clean energy and electronics.

Electronic structure and oxidation states

Lanthanide electronic structure centers on progressive filling of the 4f orbitals, a pattern first rationalized by researchers associated with the University of Cambridge and the University of Göttingen. The 4f electrons are relatively localized compared with 5d or 6s electrons, affecting spectroscopic features used in work at institutions such as the National Institute of Standards and Technology and the Fraunhofer Society. Common oxidation states include +3 for most elements in the series, with notable exceptions and variable behavior in +2 and +4 states seen in elements studied using methods from Lawrence Livermore National Laboratory and described in monographs published by Elsevier and the Royal Society of Chemistry.

Physical and chemical properties

Lanthanide metals display high densities and malleability, characteristics measured in laboratories at the Massachusetts Institute of Technology and the California Institute of Technology. They form trivalent ions that produce sharp absorption and emission lines exploited in spectroscopy at facilities such as the European Synchrotron Radiation Facility and the SLAC National Accelerator Laboratory. Magnetic properties—paramagnetism and, in certain compounds, strong ferromagnetism—have been central to advances at companies like Hitachi and research groups led by laureates of the Nobel Prize in Physics for work related to magnetic materials. Chemical reactivity includes oxidation in air and complexation with ligands studied in academic departments at Oxford University and Harvard University.

Occurrence and extraction

These elements occur in minerals such as bastnäsite, monazite, and xenotime, mined by corporations like MP Materials and national projects overseen by the Ministry of Natural Resources (China). Major deposits are found in regions including Inner Mongolia, Brazil, Madagascar, and Australia, with processing techniques developed in research collaborations between Imperial College London and industrial partners like Rio Tinto. Extraction involves solvent extraction, ion-exchange, and pyrometallurgical methods refined in pilot plants supported by the European Commission and the U.S. Department of Energy. Geopolitical events like policies from the World Trade Organization and sanctions involving Russia have influenced supply chains for these elements.

Applications and uses

Lanthanide-based materials enable technologies in permanent magnets, catalysts, phosphors, and batteries, influencing products from Tesla, Inc., Samsung, and LG Chem. Neodymium-iron-boron magnets are critical in wind turbines manufactured by firms such as Vestas Wind Systems and in electric vehicles produced by Volkswagen. Europium and terbium compounds are essential for display technologies developed by Sony and Samsung Electronics. Catalytic converters in vehicles by General Motors and Toyota employ cerium oxides researched at national laboratories like Argonne National Laboratory. Optical fibers and glass produced by companies such as Corning Incorporated incorporate these elements following studies by scholars at Bell Labs.

Environmental and biological aspects

Mining and processing create environmental challenges monitored by agencies including the Environmental Protection Agency and the United Nations Environment Programme, with remediation strategies tested by teams at Stanford University and ETH Zurich. Some lanthanide compounds show low to moderate bioavailability and limited essential biological roles, a topic of study in research from institutions like the University of Copenhagen and the Karolinska Institute. Toxicological assessments performed by the World Health Organization and national health agencies inform regulations affecting communities near mining regions such as Inner Mongolia and Brazilian Amazon sites. Recycling initiatives promoted by the European Union and corporations like Umicore aim to reduce environmental impact and secure supply chains.

Category:Chemical elements