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Free Samarium student datasheetPrintable revision sheet with identity, structure, evidence notes, phase behavior, uses, isotopes and review prompts.
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Instant reference

Samarium atomic number, mass, electron configuration and key properties

Atomic number
62
Relative atomic mass
150.36
Electron configuration
[Xe] 4f⁶ 6s²
Common oxidation states
+3, +2
Density
7.52 g/cm³
Melting point
1345 K
Boiling point
2067 K
Ordinary crystal
Sm-type rhombohedral structure
ClassificationLanthanide
Reference isotope¹⁵²Sm
State contextSilvery-white lanthanide metal
Evidence noteAtomic identity and reference values are source-reviewed. Material viewers are teaching representations, not crystallographic refinements. Search demand shapes headings and FAQs but never overrides measured/evaluated evidence or element-versus-compound distinctions.
Quick answers

Samarium: quick answers

How many protons, neutrons and electrons does samarium have?

Samarium’s atomic number is 62, so every samarium atom has 62 protons, and a neutral atom also has 62 electrons. Its most common natural isotope, samarium-152, has 90 neutrons (other isotopes have different neutron counts).

What is the symbol for samarium?

The chemical symbol for samarium is Sm.

Is samarium a solid, liquid or gas at room temperature?

Samarium is a solid at room temperature (about 25 °C).

What family (group) is samarium in?

Samarium is a lanthanide, in period 6 (the f-block row shown below the main table) of the periodic table.

What is the electron configuration of samarium?

The ground-state electron configuration of samarium is [Xe] 4f⁶ 6s².

Connect the facts

From atomic number to chemistry

Read these as a chain of causes, not as isolated facts. Each step links to the concept hub if you want the underlying idea explained.

Common misconceptionSamarium-cobalt magnets are intermetallic materials, not pieces of elemental samarium. Natural samarium also contains both stable and extremely long-lived radioactive isotopes, so “is samarium radioactive?” needs an isotope-specific answer.
Periodic-table position

Samarium in its period and family

Samarium lies near the middle of the lanthanide series. The [Xe]4f⁶6s² atom commonly forms Sm³⁺, while Sm²⁺ is accessible in selected compounds.

Interactive Visual Lab

Samarium Visual Lab

Explore Sm across the teaching nucleus, isolated-atom orbitals, evidence-aware material structure and temperature/evidence views, then connect those models to uses, isotopes, search-led questions and source-backed context.

Overview · structure · orbitals · real world
How to read an element tile

Every mark points to one exact feature

162 2150.36 3Sm 4[Xe] 4f⁶ 6s² 5Samarium 6Sm-type rhombohedral structure 7Silvery-white lan…
1Atomic numberNumber of protons
2Relative atomic massStandard value or bracketed reference mass
3Chemical symbolSm
4Electron configurationGround-state shorthand or evidence-labelled prediction
5Element nameSamarium
6Structure contextSm-type rhombohedral structure
7Physical-state contextSilvery-white lanthanide metal

The numbered markers explain the same information system used throughout Element Lookup. Unknown or predicted fields remain visibly labelled rather than being replaced with guesses.

Five things worth remembering

Samarium in one minute

01

Atomic number 62 means every samarium nucleus has 62 protons.

02

Neutral Samarium has the ground-state configuration [Xe] 4f⁶ 6s².

03

The representative teaching isotope is ¹⁵²Sm.

04

Samarium-cobalt magnets are intermetallic materials, not pieces of elemental samarium.

05

The ordinary material reference is Sm-type rhombohedral structure.

Atomic structure teaching model

¹⁵²Sm nucleus · neutral Sm

Nucleus modelNucleon-count teaching view
62 p⁺ + 90 n⁰¹⁵²Sm · schematic nucleus, not a literal nuclear geometry
Electron-count schematicPrincipal-shell populations

Shell rings organize electron counts. They are not electron trajectories or orbital shapes.

Nucleus, shell count and material structure are deliberately separated so one picture is not mistaken for another.
Connect picture → chemistry

2 · 8 · 18 · 24 · 8 · 2 electrons

n=12
n=28
n=318
n=424
n=58
n=62
Why this electron pattern matters

The displayed 4f_xyz orbital is one representative real f cubic harmonic. It is not a picture of the whole 4f subshell or the electronic bands in the bulk material.

Teaching boundary: the nucleus uses colored spheres to make proton/neutron counts visible; the shell diagram only summarizes principal-shell populations. Neither is a literal picture of electron motion.
Material / molecular structure viewer

Sm-type rhombohedral structure

Samarium has its namesake Sm-type rhombohedral structure at ordinary temperature. The viewer uses a simplified rhombohedral teaching motif rather than pretending to reproduce the full crystallographic basis.
Sm-type rhombohedral structureSamarium has its namesake Sm-type rhombohedral structure at ordinary temperature. The viewer uses a simplified rhombohedral teaching motif rather than pretending to reproduce the full crystallographic basis.
What are you seeing?

Samarium has its namesake Sm-type rhombohedral structure at ordinary temperature. The viewer uses a simplified rhombohedral teaching motif rather than pretending to reproduce the full crystallographic basis.. The viewer is evidence-aware: measured structures are identified as such; unknown bulk structures stay unknown.

Teaching visualization; not a literal finite sample or thermal trajectory.
Probability-cloud teaching model

4f xyz orbital

One-electron teaching approximation; dots represent sampled probability density, not individual electrons.
Interpretation

What this model does—and does not—show

The displayed 4f_xyz orbital is one representative real f cubic harmonic. It is not a picture of the whole 4f subshell or the electronic bands in the bulk material.

Important: The cloud includes the expected nodal pattern for the named nonrelativistic orbital where applicable. Phase colors are not electric charge. For heavy and superheavy elements, relativistic/many-electron effects make these only teaching approximations.
Real-world archive

Where do I meet samarium?

Clickable learning cards connect the element to materials, environment, technology, biology or research - depending on what the evidence actually supports.

One
Sm-Co magnets

Sm-Co magnets

Samarium-cobalt intermetallic magnets offer strong permanent magnetism with good high-temperature performance.

1879Paul-Émile Lecoq de Boisbaudran identified samarium spectroscopically from material related to samarskite.
Late 19th centuryRare-earth separation and spectroscopy established samarium as distinct from neighboring lanthanides.
20th centurySm-Co intermetallics became important permanent-magnet materials.
TodaySamarium remains a specialized magnet, neutron and optical material element.
Evidence principleAtomic identity and reference values are source-reviewed. Material viewers are teaching representations, not crystallographic refinements. Search demand shapes headings and FAQs but never overrides measured/evaluated evidence or element-versus-compound distinctions.
Signature science

4f⁶ → Sm³⁺ → Sm-Co permanent magnets

Samarium-cobalt magnets derive their performance from ordered Sm-Co intermetallic phases, not elemental samarium alone. Natural samarium also contains both stable and extremely long-lived radioactive isotopes.

Evaluated

4f⁶6s²

One electron short of half-filled 4f⁷.

Reference properties

Samarium properties: atomic, physical, thermal and chemical

Categories follow the science of this element rather than a fixed decorative template. Each row carries condition/provenance context and an evidence label; unknown values stay unknown.

PropertyValueContext / provenanceEvidence
Atomic number62Source-reviewed; see Sources belowEvaluated
Relative atomic mass150.36Source-reviewed; see Sources belowEvaluated
Ground-state electron configuration[Xe] 4f⁶ 6s²Source-reviewed; see Sources belowEvaluated
Group / period / blockGroup Lanthanide · Period 6 · f-blockPeriodic-table placementEvaluated
Electronegativity1.17Source-reviewed; see Sources belowEvaluated
Reference isotope¹⁵²SmSource-reviewed; see Sources belowEvaluated
PropertyValueContext / provenanceEvidence
State contextSilvery-white lanthanide metalSource-reviewed; see Sources belowEvaluated
Density7.52 g/cm³Source-reviewed; see Sources belowEvaluated
Material / molecular structureSm-type rhombohedral structureSamarium has its namesake Sm-type rhombohedral structure at ordinary temperature. The viewer uses a simplified rhombohedral teaching motif rather than pretending to reproduce the full crystallographic basis.Measured
ClassificationLanthanidePeriodic-table / chemistry classificationEvaluated
Structure-model scopeSamarium has its namesake Sm-type rhombohedral structure at ordinary temperature. The viewer uses a simplified rhombohedral teaching motif rather than pretending to reproduce the full crystallographic basis.Teaching visualization; exact crystallographic coordinates are not implied unless stated.Reviewed
PropertyValueContext / provenanceEvidence
Melting / transition reference1345 KSource-reviewed; see Sources belowEvaluated
Boiling / gas reference2067 KSource-reviewed; see Sources belowEvaluated
Phase-path contextAt approximately standard pressure, samarium is treated as a solid below 1345 K, liquid between melting and approximately 2067 K, and gas above the boiling reference. The ordinary crystal label applies to the stated material reference; unmodeled solid allotropy is not fabricated.Shared phase registry drives the slider, regions and markers.Evaluated
Condition warningTemperature and pressure define phase behavior; purity/allotropy may matter.Teaching condition statementReviewed
PropertyValueContext / provenanceEvidence
Common oxidation states+3, +2Source-reviewed; see Sources belowEvaluated
Ion / common ion contextSm³⁺Source-reviewed; see Sources belowEvaluated
Periodic chemistry contextSamarium lies near the middle of the lanthanide series. The [Xe]4f⁶6s² atom commonly forms Sm³⁺, while Sm²⁺ is accessible in selected compounds.Element-specific interpretationReviewed
Chemistry cautionElemental form, ions and compounds are distinct chemical objects.Interpretive teaching ruleReviewed
PropertyValueContext / provenanceEvidence
¹⁵²SmMost abundant natural isotopeStable reference isotope used for the teaching nucleus.Evaluated
¹⁴⁷SmLong-lived natural radioisotopeUsed in Sm-Nd geochronology because of its very long alpha-decay timescale.Evaluated
Natural samariumMixed isotope setIncludes stable and extremely long-lived radioactive isotopes.Evaluated
Teaching nucleus¹⁵²Sm · 62 protons + 90 neutronsReference isotope used in the nucleus modelReviewed
PropertyValueContext / provenanceEvidence
Page evidence noteAtomic identity and reference values are source-reviewed. Material viewers are teaching representations, not crystallographic refinements. Search demand shapes headings and FAQs but never overrides measured/evaluated evidence or element-versus-compound distinctions.Evidence summary for this guideReviewed
Structure evidenceSamarium has its namesake Sm-type rhombohedral structure at ordinary temperature. The viewer uses a simplified rhombohedral teaching motif rather than pretending to reproduce the full crystallographic basis.Measured structure, labelled schematic, prediction or explicit unknown as applicable.Reviewed
Map evidence ruleReal pins are reviewed examples; conceptual layers are used when pins would mislead.Geography Explorer 2.0Reviewed
Source set3 primary/reference links listed belowOpen the Sources section for the actual references.Reviewed
Temperature explorer

Is Samarium a solid, liquid or gas? State at temperature

At approximately standard pressure, samarium is treated as a solid below 1345 K, liquid between melting and approximately 2067 K, and gas above the boiling reference. The ordinary crystal label applies to the stated material reference; unmodeled solid allotropy is not fabricated.

Temperature293 K
Move the slider
The shared site-wide phase model controls the track, markers and readout.
Geography and evidence

Where on Earth is Samarium found or produced?

World map
Paris, FranceRSC historical context · historical
Discovery and history

Who discovered Samarium, and when?

1879

Paul-Émile Lecoq de Boisbaudran identified samarium spectroscopically from material related to samarskite.

Late 19th century

Rare-earth separation and spectroscopy established samarium as distinct from neighboring lanthanides.

20th century

Sm-Co intermetallics became important permanent-magnet materials.

Today

Samarium remains a specialized magnet, neutron and optical material element.

Process / synthesis context

From source material to Samarium applications: high-level material path

1

Samarium is obtained from mineral or metallurgical feedstocks in which it is chemically associated with other elements rather than mined as abundant native metal.

2

Industrial separation and refining produce element-specific compounds or metal feedstock; this guide does not provide operational extraction recipes.

3

The refined material is converted into the particular alloy, compound, doped host or component required by the application.

4

Recycling and recovery depend on the host product, concentration and economics; application materials must not be confused with pure element.

Safety boundary: This page is educational. Chemical, occupational, radiological or medical safety decisions require the specific material/isotope, its current safety data and qualified guidance.
Real-world applications

What is samarium used for?

Sm-Co magnets

Samarium-cobalt magnets combine high magnetic performance with useful high-temperature stability.

Neutron absorbers

High neutron-capture isotopes make samarium useful in selected nuclear-material contexts.

Optics

Samarium-doped glasses and crystals provide characteristic optical transitions.

Research chemistry

Sm compounds such as Sm(II) reagents are important in specialized chemical synthesis and research.

Isotopes

Samarium isotopes and natural abundance

¹⁵²Sm

Most abundant natural isotope

Stable reference isotope used for the teaching nucleus.

¹⁴⁷Sm

Long-lived natural radioisotope

Used in Sm-Nd geochronology because of its very long alpha-decay timescale.

Natural samarium

Mixed isotope set

Includes stable and extremely long-lived radioactive isotopes.

Learn it, don’t just read it

Five-question Samarium check

What is Samarium’s atomic number?

Which classification best fits Samarium?

What is the representative teaching isotope?

Which statement respects the material evidence?

Which rule should guide real-world uses?

Questions answered

Samarium questions students commonly ask

Each answer starts with the direct fact, then explains the chemistry, evidence or material context so the result is understandable rather than merely memorized.

What is samarium?

Short answer: Samarium is chemical element 62, symbol Sm, a silvery lanthanide metal.

Atomic number 62 means every samarium nucleus contains 62 protons. In the periodic table, Samarium is classified here as a lanthanide in Period 6 and Group Lanthanide. Samarium lies near the middle of the lanthanide series. The [Xe]4f⁶6s² atom commonly forms Sm³⁺, while Sm²⁺ is accessible in selected compounds.

Key point: Sm is element 62; its periodic position and electron structure explain the rest of the page.

What is samarium used for?

Short answer: Major uses include samarium-cobalt magnets, neutron-absorbing materials, optical materials and specialized chemistry.

Sm-Co magnets: Samarium-cobalt magnets combine high magnetic performance with useful high-temperature stability. Neutron absorbers: High neutron-capture isotopes make samarium useful in selected nuclear-material contexts. Samarium-cobalt magnets are intermetallic materials, not pieces of elemental samarium. Natural samarium also contains both stable and extremely long-lived radioactive isotopes, so “is samarium radioactive?” needs an isotope-specific answer.

Key point: Always distinguish the pure element from the compound, alloy, isotope or device material that actually performs the application.

Where is samarium found?

Short answer: It occurs with other lanthanides in minerals such as monazite and bastnäsite and is separated during rare-earth processing.

Samarium is obtained from mineral or metallurgical feedstocks in which it is chemically associated with other elements rather than mined as abundant native metal. Late 19th century Rare-earth separation and spectroscopy established samarium as distinct from neighboring lanthanides.

Key point: Natural occurrence, resources, production and recycling are different geography questions.

Who discovered samarium?

Short answer: Paul-Émile Lecoq de Boisbaudran identified samarium in 1879.

In 1879, Paul-Émile Lecoq de Boisbaudran identified samarium spectroscopically from material related to samarskite. In the late 19th century, Rare-earth separation and spectroscopy established samarium as distinct from neighboring lanthanides.

Key point: Discovery credit follows the historical evidence and accepted attribution, not just the earliest claim.

Is samarium a metal?

Short answer: Yes. It is a lanthanide metal.

This guide classifies Samarium as a lanthanide. Its periodic position is Period 6, f-block, Group Lanthanide. Samarium lies near the middle of the lanthanide series. The [Xe]4f⁶6s² atom commonly forms Sm³⁺, while Sm²⁺ is accessible in selected compounds.

Key point: Periodic-table classification describes recurring atomic/chemical behavior; it does not make every element in a column physically identical.

Is samarium radioactive?

Short answer: Natural samarium contains both stable isotopes and extremely long-lived radioactive isotopes such as ¹⁴⁷Sm.

¹⁵²Sm: Most abundant natural isotope: Stable reference isotope used for the teaching nucleus. ¹⁴⁷Sm: Long-lived natural radioisotope: Used in Sm-Nd geochronology because of its very long alpha-decay timescale.

Key point: Radioactivity is isotope-specific; do not apply one isotope’s nuclear behavior to every atom of the element.

What are samarium-cobalt magnets?

Short answer: They are intermetallic Sm-Co magnet materials; their properties belong to the compound/alloy phases, not pure Sm metal alone.

Samarium-cobalt magnets are intermetallic materials, not pieces of elemental samarium. Samarium-cobalt magnets are intermetallic materials, not pieces of elemental samarium. Natural samarium also contains both stable and extremely long-lived radioactive isotopes, so “is samarium radioactive?” needs an isotope-specific answer.

Key point: The mechanism matters: connect the observed behavior to electron structure, bonding, phase or the specific material form rather than memorizing the result alone.

How many electrons does samarium have?

Short answer: A neutral samarium atom has 62 electrons with ground-state configuration [Xe] 4f⁶ 6s².

A neutral atom has the same number of electrons as protons, so neutral Samarium has 62 electrons. Its ground-state reference configuration is [Xe] 4f⁶ 6s²; ions have different electron counts because electrons have been removed or added.

Key point: Electron count changes in ions; proton count does not.

Scientific sources and provenance

Scientific sources for Samarium

Evidence rule: Atomic identity and reference values are source-reviewed. Material viewers are teaching representations, not crystallographic refinements. Search demand shapes headings and FAQs but never overrides measured/evaluated evidence or element-versus-compound distinctions.
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