Chemical element · Atomic number 62

Samarium

Samarium in the periodic table: atomic number 62, electron configuration, atomic mass, physical data, oxidation states, media credit and visible sources.

Sm

Lanthanide

solid

150.4 u

About six grams of oxidised samarium shards broken off a larger pieceDocumented element sample

About six grams of oxidised samarium shards taken from a larger piece.

Image credit: brainandforce

Auto-oriented, limited to 1600 × 1200 pixels and re-encoded as WebP; the subject was not altered.

Commons fileLicence: Public Domain

Atomic classification

Samarium in the Bohr shell modelThis shows the electron distribution of the neutral atom in a simplified shell model.: 2 · 8 · 18 · 24 · 8 · 2

Shell occupancy

Samarium in the Bohr shell model

This shows the electron distribution of the neutral atom in a simplified shell model.

K · n=1
2 electrons
L · n=2
8 electrons
M · n=3
18 electrons
N · n=4
24 electrons
O · n=5
8 electrons
P · n=6
2 electrons
Shell occupancy is derived from the versioned PubChem electron configuration. Dot angles are schematic and do not represent orbitals.
Electron configuration
[Xe]6s2 4f6
Electrons per shell
2 · 8 · 18 · 24 · 8 · 2
Group
not reported
Period
6
Block
F
Element category
Lanthanide

Physical and chemical properties

Atomic mass
150.4 u
Standard state
solid
Density
7.52 g/cm³
Melting point
1,347 K
Boiling point
2,067 K
Electronegativity
1.17 (Pauling)
First ionisation energy
5.644 eV
Oxidation states
+3, +2
Discovery
1879

Safety and periodic classification

Safety

Safe handling cannot be inferred from Samarium's position in the periodic table alone. Laboratory, classroom and disposal decisions must follow the documentation for the exact material and its safety data sheet.

Position and comparison

Samarium is in period 6 and the F block. Its direct neighbours by atomic number are Promethium and Europium. The recorded Pauling electronegativity is 1.17. Periodic trends are compared only through the separately sourced neighbouring values.

Sources and scope

PubChem attributes element data to sources including IUPAC, NIST and IAEA. Quanta stores the referenced snapshot locally and leaves unknown values unavailable.

Where Samarium sits among the 118 elements

The table compares the reported values for Samarium with every other element that carries the same value in the snapshot. A rank is not a judgement, it is orientation: it says how unusual this value is across the periodic table.

ValueSamariumPosition in the data set
Melting point1,347 KRank 43 of 103 elements with a reported value. Highest: Carbon.
Boiling point2,067 KRank 56 of 93 elements with a reported value. Highest: Rhenium.
Density7.52 g/cm³Rank 42 of 96 elements with a reported value. Highest: Osmium.
Electronegativity (Pauling)1.17Rank 80 of 95 elements with a reported value. Highest: Fluorine.
Ionisation energy5.644 eVRank 87 of 102 elements with a reported value. Highest: Helium.

All values and ranks come from the PubChem Periodic Table snapshot, retrieved on 2026-07-15. Elements without a reported value are excluded, so the population differs per row.

The neighbours of Samarium in the periodic table

Place in the table
No group number, period 6, F block. Classified as lanthanide, solid at standard conditions.
Direct neighbours
Atomic number 62. Preceded by Promethium, followed by Europium.
Discovery
Recorded in the snapshot as: 1879. Who, where and under what circumstances is not part of that record, so this page carries the sourced year and no discovery narrative.
Oxidation states
+3, +2. They follow from the electron configuration [Xe]6s2 4f6 and indicate which compounds to expect.

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