lanthanide
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Definition
- Noun:
- A chemical element belonging to the lanthanide series: A lanthanide is any of a series of 15 metallic chemical elements with atomic numbers 57 through 71. They are known for their similar chemical properties, high density, and typically shiny, silvery-white appearance. They are often found together in mineral deposits.
Usage
- The term lanthanide is used primarily in scientific contexts, specifically in chemistry, geology, and materials science.
- It functions as a countable noun (e.g., , ).
- It is often used attributively as a noun modifier (e.g., , ).
Examples
- Noun:
- Europium is a lanthanide used in the phosphors of television screens.
- The lanthanides are sometimes called the rare-earth elements.
- Scientists are studying the magnetic properties of this particular lanthanide.
Advanced Usage
- "Lanthanide contraction": A phenomenon in chemistry where the atomic radii of the lanthanide elements decrease more than expected across the series, influencing the properties of subsequent elements in the periodic table.
- The lanthanide contraction explains the similar sizes of zirconium and hafnium.
Variants and Related Words
- Lanthanoid (noun): A synonym for lanthanide, often preferred in IUPAC nomenclature.
- Rare-earth element (noun): A broader category that includes the lanthanides plus scandium and yttrium. While not perfectly synonymous, the terms are often used interchangeably in non-technical contexts.
Synonyms
- Rare-earth element (in broad, non-technical usage)
- Lanthanoid
Related Phrases and Terms
- Lanthanide series (noun phrase): The specific group of 15 consecutive elements in the periodic table to which lanthanides belong.
- The lanthanide series spans from lanthanum to lutetium.
- Inner transition metal (noun phrase): A category of metallic elements that includes both the lanthanide and actinide series.
Noun
- any element of the lanthanide series (atomic numbers 57 through 71)