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About Samarium

Samarium Bohr

In 1839, a German mineralogist named Gustav Rose described a new mineral in samples provided to him by a Russian mining engineer named Samarsky-Bykhovets. The mineral was eventually named samarskite after its discoverer. When French chemist Paul Emile Lecoq de Boisbaudran isolated an oxide of a new element from the mineral in 1879, he named it after the mineral, making samarium the first chemical element to be named, if somewhat indirectly, after an individual. Though the pure metal could not be easily obtained in quantities sufficient for commercial use until the 1950s, a byproduct of the purification of other rare earths with a high percentage of samarium did find early use in control rods for some of the first nuclear reactors.

Today samarium is used in a number of applications, the most significant of which is high-strength samarium-cobalt magnets. These magnets are slightly surpassed in strength by neodymium magnets, but are preferred in some applications due to their ability to maintain their magnetic properties at significantly higher temperatures. These magnets are frequently found in small motors, speakers, and other electronic devices. Another significant commercial use is catalysis. Samarium catalysts are used in a variety of industrial processes including decomposition of plastics, dechlorination of pollutants, and dehydration of ethanol. Additionally, a variety of samarium compounds are used as catalysts and reagents in organic synthesis. Samarium can be also be used to provide useful properties to a substrate material such as glass when added in small quantities during production, a process often referred to as doping. Samarium oxide is added to ceramics and glasses to increase absorption of infrared light. Samarium-doped crystals have been used as gain media for lasers since the one of the first solid-state lasers was produced by IBM research labs in 1961, and in 1997 a samarium-based gain media was used to produce the first saturated x-ray laser.

Several specific isotopes of samarium have specialized uses. The radioactive isotope samarium-153 is used in the treatment of some advanced cancers, as it naturally localizes to the bones and emits beta particles that kill the nearby cancer cells, lessening the extreme pain of bone metastases. Samarium-149 is notable for being an excellent absorber of neutrons, and is used in this capacity in the control rods of nuclear reactors. Additionally, relative ratios of samarium-147 and its decay product neodymium-143 can be measured and used to estimate the age of objects that are billions of years old.

Finally, there are a number of samarium applications still under development. A group of compounds called samarium monochalcogenides are crystalline semiconducting solids with interesting properties. In particular, the electrical properties of the solids change depending on the pressure applied to the material, and the material generates electric voltage when heated. These unique phenomena are being investigated for use in pressure sensors, memory devices, and thermoelectric power converters. Samarium can be used in the production of superconducting materials, and samarium-doped iron superconductors are among the highest-temperature superconductors known. Samarium-doped cerium oxide nanostructures are of interest for use in solid oxide fuel cells.

Samarium is a rare earth element and is found along with other elements of this group in a variety of rare earth minerals. The primary commercial sources are the minerals monazite and bastnasite.


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Elemental Samarium Picture

Samarium is primarily utilized in the production of samarium-cobalt (Sm2Co17) permanent magnets. It is also used in laser applications and for its dielectric properties. Samarium-cobalt magnets replaced the more expensive platinum-cobalt magnets in the early 1970s. While now overshadowed by the even stronger neodymium-iron-boron magnet, they are still valued for their ability to functionHigh Purity (99.999%) Samarium Oxide (Sm2O3) Powder at high temperatures. They are utilized in lightweight electronic equipment where size or space is a limiting factor and where functionality at high temperature is a concern. Applications include electronic watches, aeospace equipment, microwave technology and servomotors.High Purity (99.999%) Samarium (Sm) Sputtering Target Samarium is available as metal and compounds with purities from 99% to 99.999% (ACS grade to ultra-high purity). Elemental or metallic forms include pellets, rod, wire and granules for evaporation source material purposes. Samarium oxides are available in powder and dense pellet form for such uses as optical coating and thin film applications. Oxides tend to be insoluble. Fluorides are another insoluble form for uses in which oxygen is undesirable such as metallurgy, chemical and physical vapor deposition and in some optical coatings. Samarium is also available in soluble forms including chlorides, nitrates and acetates. These compounds can be manufactured as solutions at specified stoichiometries.

Samarium Properties

Samarium (Sm) atomic and molecular weight, atomic number and elemental symbolSamarium is a Block F, Group 3, Period 6 element. Samarium Bohr ModelThe number of electrons in each of Samarium's shells is 2, 8, 18, 24, 8, 2 and its electron configuration is [Xe]4f6 6s2. The samarium atom has a radius of and its Van der Waals radius is In its elemental form, CAS 7440-19-9, samarium has a silvery-white appearance. Samarium was discovered and first isolated by Lecoq de Boisbaudran in 1879. It is named after the mineral samarskite.

Symbol: Sm
Atomic Number: 62
Atomic Weight: 150.36
Element Category: Lanthanide
Group, Period, Block: n/a, 6, f
Color: silvery-white
Other Names: Samario
Melting Point: 1072°C, 1961.6°F, 1345.15 K
Boiling Point: 1794°C, 3261.2°F, 2067.15 K
Density: 7353 kg/m3
Liquid Density @ Melting Point: 7.16 g·cm3
Density @ 20°C: 7.54 g/cm3
Density of Solid: 7353 kg·m3
Specific Heat: 0.043 Cal/g/K @ 25 °C
Superconductivity Temperature: N/A
Triple Point: N/A
Critical Point: N/A
Heat of Fusion (kJ·mol-1): 10.9
Heat of Vaporization (kJ·mol-1): 164.8
Heat of Atomization (kJ·mol-1): 206.1
Thermal Conductivity: 0.133 W/cm/K @ 298.2 K
Thermal Expansion: (r.t.) ( poly) 12.7 µm/(m·K)
Electrical Resistivity: 88.0 µΩ-cm @ 25°C
Tensile Strength: N/A
Molar Heat Capacity: 29.54 J·mol-1·K-1
Young's Modulus: (? form) 49.7 GPa
Shear Modulus: (? form) 19.5 GPa
Bulk Modulus: (? form) 37.8 GPa
Poisson Ratio: (? form) 0.274
Mohs Hardness: N/A
Vickers Hardness: 412 MPa
Brinell Hardness: 441 MPa
Speed of Sound: (20 °C) 2130 m·s-1
Pauling Electronegativity: 1.17
Sanderson Electronegativity: N/A
Allred Rochow Electronegativity: 1.07
Mulliken-Jaffe Electronegativity: N/A
Allen Electronegativity: N/A
Pauling Electropositivity: 2.83
Reflectivity (%): N/A
Refractive Index: N/A
Electrons: 62
Protons: 62
Neutrons: 88
Electron Configuration: [Xe]4f6 6s2
Atomic Radius: 180 pm
Atomic Radius,
non-bonded (Å):
Covalent Radius: 198±8 pm
Covalent Radius (Å): 1.85
Van der Waals Radius: 229 pm
Oxidation States: 4, 3, 2, 1 (mildly basic oxide)
Phase: Solid
Crystal Structure: rhombohedral
Magnetic Ordering: paramagnetic
Electron Affinity (kJ·mol-1) Unknown
1st Ionization Energy: 544.53 kJ·mol-1
2nd Ionization Energy: 1068.10 kJ·mol-1
3rd Ionization Energy: 2257.77 kJ·mol-1
CAS Number: 7440-19-9
EC Number: 231-128-7
MDL Number: MFCD00011233
Beilstein Number: N/A
SMILES Identifier: [Sm]
InChI Identifier: InChI=1S/Sm
PubChem CID: 23951
ChemSpider ID: 22391
Earth - Total: 208 ppb
Mercury - Total: 160 ppb 
Venus - Total: 218 ppb 
Earth - Seawater (Oceans), ppb by weight: 0.00045
Earth - Seawater (Oceans), ppb by atoms: 0.000019
Earth -  Crust (Crustal Rocks), ppb by weight: 6000
Earth -  Crust (Crustal Rocks), ppb by atoms: 820
Sun - Total, ppb by weight: 1
Sun - Total, ppb by atoms: 0.01
Stream, ppb by weight: 0.03
Stream, ppb by atoms: 0.0002
Meterorite (Carbonaceous), ppb by weight: 170
Meterorite (Carbonaceous), ppb by atoms: 20
Typical Human Body, ppb by weight: N/A
Typical Human Body, ppb by atom: N/A
Universe, ppb by weight: 5
Universe, ppb by atom: 0.04
Discovered By: Lecoq de Boisbaudran
Discovery Date: 1879
First Isolation: Lecoq de Boisbaudran (1879)

Health, Safety & Transportation Information for Samarium

Samarium is somewhat toxic. Safety data for Samarium and its compounds can vary widely depending on the form. For potential hazard information, toxicity, and road, sea and air transportation limitations, such as DOT Hazard Class, DOT Number, EU Number, NFPA Health rating and RTECS Class, please see the specific material or compound referenced in the Products tab. The below information applies to elemental (metallic) Samarium.

Safety Data
Signal Word Danger
Hazard Statements H228-H261-H373
Hazard Codes R
Risk Codes 15-33
Safety Precautions 30
RTECS Number N/A
Transport Information UN 2910 7
WGK Germany 3
Globally Harmonized System of
Classification and Labelling (GHS)
Flame-Flammables Health Hazard
Review and Print SDS for Samarium Metal


Date Created: 05/15/2015
Date Revised: 05/15/2015


Product Name: Samarium Metal

Product Number: All applicable American Elements product codes, e.g. SM-M-02, SM-M-03, SM-M-04, SM-M-05

CAS #: 7440-19-9

Relevant identified uses of the substance: Scientific research and development

Supplier details:
American Elements
1093 Broxton Ave. Suite 2000
Los Angeles, CA 90024
Tel: +1 310-208-0551
Fax: +1 310-208-0351

Emergency telephone number:
Domestic, North America +1 800-424-9300
International +1 703-527-3887


Classification of the substance or mixture
Classification according to Regulation (EC) No 1272/2008
The substance is not classified as hazardous to health or the environment according to the CLP regulation.
Classification according to Directive 67/548/EEC or Directive 1999/45/EC
Not applicable
Information concerning particular hazards for human and environment:
No information known.
Hazards not otherwise classified
No information known.
Label elements
Labelling according to Regulation (EC) No 1272/2008
Not applicable
Hazard pictograms
Not applicable
Signal word
Not applicable
Hazard statements
Not applicable
WHMIS classification
Not controlled
Classification system
HMIS ratings (scale 0-4)
(Hazardous Materials Identification System)
Health (acute effects) = 1
Flammability = 1
Physical Hazard = 1
Other hazards
Results of PBT and vPvB assessment
Not applicable.
Not applicable.


Chemical characterization: Substances
CAS# Description:
7440-19-9 Samarium
Identification number(s):
EC number:


Description of first aid measures
General information
No special measures required.
After inhalation
Seek medical treatment in case of complaints.
After skin contact
Generally the product does not irritate the skin.
After eye contact
Rinse opened eye for several minutes under running water. If symptoms persist, consult a doctor.
After swallowing
If symptoms persist consult doctor.
Information for doctor
Most important symptoms and effects, both acute and delayed
No further relevant information available.
Indication of any immediate medical attention and special treatment needed
No further relevant information available.


Extinguishing media
Suitable extinguishing agents
Special powder for metal fires. Do not use water.
For safety reasons unsuitable extinguishing agents
Special hazards arising from the substance or mixture
If this product is involved in a fire, the following can be released:
Metal oxide fume
Advice for firefighters
Protective equipment:
No special measures required.


Personal precautions, protective equipment and emergency procedures
Not required.
Environmental precautions:
Do not allow material to be released to the environment without proper governmental permits.
Do not allow product to reach sewage system or any water course.
Do not allow to penetrate the ground/soil.
Methods and material for containment and cleaning up:
Pick up mechanically
Prevention of secondary hazards:
No special measures required.
Reference to other sections
See Section 7 for information on safe handling
See Section 8 for information on personal protection equipment.
See Section 13 for disposal information.


Precautions for safe handling
Handle under dry protective gas.
Keep container tightly sealed.
Store in cool, dry place in tightly closed containers.
Information about protection against explosions and fires:
No special measures required.
Conditions for safe storage, including any incompatibilities
Requirements to be met by storerooms and receptacles:
No special requirements.
Information about storage in one common storage facility:
Store away from oxidizing agents.
Do not store together with acids.
Store away from acid chlorides.
Store away from halogens.
Store away from air.
Store away from water/moisture.
Further information about storage conditions:
Store under dry inert gas.
This product is moisture sensitive.
This product is air sensitive.
Keep container tightly sealed.
Store in cool, dry conditions in well sealed containers.
Protect from humidity and water.
Specific end use(s)
No further relevant information available.


Additional information about design of technical systems:
No further data; see section 7.
Control parameters
Components with limit values that require monitoring at the workplace:
The product does not contain any relevant quantities of materials with critical values that have to be monitored at the workplace.
Additional information:
No data
Exposure controls
Personal protective equipment
General protective and hygienic measures
The usual precautionary measures for handling chemicals should be followed.
Maintain an ergonomically appropriate working environment.
Breathing equipment:
Not required.
Protection of hands:
Not required.
Penetration time of glove material (in minutes)
Not determined
Eye protection:
Safety glasses
Body protection:
Protective work clothing


Information on basic physical and chemical properties
General Information
Form: Solid in various forms
Color: Silver grey
Odor: Odorless
Odor threshold: Not determined.
pH-value: Not applicable.
Change in condition
Melting point/Melting range: 1072 °C (1962 °F)
Boiling point/Boiling range: 1794 °C (3261 °F)
Sublimation temperature / start: Not determined
Flammability (solid, gaseous)
Not determined.
Ignition temperature: Not determined
Decomposition temperature: Not determined
Auto igniting: Not determined.
Danger of explosion: Not determined.
Explosion limits:
Lower: Not determined
Upper: Not determined
Vapor pressure: Not applicable.
Density at 20 °C (68 °F): 7.52 g/cm³ (62.754 lbs/gal)
Relative density
Not determined.
Vapor density
Not applicable.
Evaporation rate
Not applicable.
Solubility in / Miscibility with Water: Insoluble
Partition coefficient (n-octanol/water): Not determined.
dynamic: Not applicable.
kinematic: Not applicable.
Other information
No further relevant information available.


No information known.
Chemical stability
Stable under recommended storage conditions.
Thermal decomposition / conditions to be avoided:
Decomposition will not occur if used and stored according to specifications.
Possibility of hazardous reactions
No dangerous reactions known
Conditions to avoid
No further relevant information available.
Incompatible materials:
Oxidizing agents
Acid chlorides
Hazardous decomposition products:
Metal oxide fume


Information on toxicological effects
Acute toxicity:
No effects known.
LD/LC50 values that are relevant for classification:
No data
Skin irritation or corrosion:
No irritant effect.
Eye irritation or corrosion:
No irritant effect.
No sensitizing effects known.
Germ cell mutagenicity:
No effects known.
No classification data on carcinogenic properties of this material is available from the EPA, IARC, NTP, OSHA or ACGIH.
Reproductive toxicity:
No effects known.
Specific target organ system toxicity - repeated exposure:
No effects known.
Specific target organ system toxicity - single exposure:
No effects known.
Aspiration hazard:
No effects known.
Subacute to chronic toxicity:
No effects known.
Additional toxicological information:
To the best of our knowledge the acute and chronic toxicity of this substance is not fully known.


Aquatic toxicity:
No further relevant information available.
Persistence and degradability
No further relevant information available.
Bioaccumulative potential
No further relevant information available.
Mobility in soil
No further relevant information available.
Additional ecological information:
General notes:
Do not allow material to be released to the environment without proper governmental permits.
Avoid transfer into the environment.
Results of PBT and vPvB assessment
Not applicable.
Not applicable.
Other adverse effects
No further relevant information available.


Waste treatment methods
Consult state, local or national regulations to ensure proper disposal.
Uncleaned packagings:
Disposal must be made according to official regulations.


Not applicable
UN proper shipping name
Not applicable
Transport hazard class(es)
Not applicable
Packing group
Not applicable
Environmental hazards:
Not applicable.
Special precautions for user
Not applicable.
Transport in bulk according to Annex II of MARPOL73/78 and the IBC Code
Not applicable.
Transport/Additional information:
Marine Pollutant (DOT):


Safety, health and environmental regulations/legislation specific for the substance or mixture
National regulations
All components of this product are listed in the U.S. Environmental Protection Agency Toxic Substances Control Act Chemical substance Inventory.
All components of this product are listed on the Canadian Domestic Substances List (DSL).
SARA Section 313 (specific toxic chemical listings)
Substance is not listed.
California Proposition 65
Prop 65 - Chemicals known to cause cancer
Substance is not listed.
Prop 65 - Developmental toxicity
Substance is not listed.
Prop 65 - Developmental toxicity, female
Substance is not listed.
Prop 65 - Developmental toxicity, male
Substance is not listed.
Information about limitation of use:
For use only by technically qualified individuals.
Other regulations, limitations and prohibitive regulations
Substance of Very High Concern (SVHC) according to the REACH Regulations (EC) No. 1907/2006.
Substance is not listed.
The conditions of restrictions according to Article 67 and Annex XVII of the Regulation (EC) No 1907/2006 (REACH) for the manufacturing, placing on the market and use must be observed.
Substance is not listed.
Annex XIV of the REACH Regulations (requiring Authorisation for use)
Substance is not listed.
REACH - Pre-registered substances
Substance is listed.
Chemical safety assessment:
A Chemical Safety Assessment has not been carried out.


Safety Data Sheet according to Regulation (EC) No. 1907/2006 (REACH). The above information is believed to be correct but does not purport to be all inclusive and shall be used only as a guide. The information in this document is based on the present state of our knowledge and is applicable to the product with regard to appropriate safety precautions. It does not represent any guarantee of the properties of the product. American Elements shall not be held liable for any damage resulting from handling or from contact with the above product. See reverse side of invoice or packing slip for additional terms and conditions of sale. COPYRIGHT 1997-2016 AMERICAN ELEMENTS. LICENSED GRANTED TO MAKE UNLIMITED PAPER COPIES FOR INTERNAL USE ONLY.

Samarium Isotopes

Samarium (Sm) has five stable isotopes: 144Sm, 149Sm, 150Sm, 152Sm and 154Sm.

Nuclide Isotopic Mass Half-Life Mode of Decay Nuclear Spin Magnetic Moment Binding Energy (MeV) Natural Abundance
(% by atom)
128Sm 127.95808(54)# 0.5# s Unknown 0+ N/A 1011.09 -
129Sm 128.95464(54)# 550(100) ms Unknown 5/2+# N/A 1019.17 -
130Sm 129.94892(43)# 1# s ß+ to 130Pm 0+ N/A 1036.56 -
131Sm 130.94611(32)# 1.2(2) s ß+ to 131Pm; ß+ + p to 130Nd 5/2+# N/A 1044.64 -
132Sm 131.94069(32)# 4.0(3) s ß+ to 132Pm; ß+ + p to 131Nd 0+ N/A 1052.72 -
133Sm 132.93867(21)# 2.90(17) s ß+ to 133Pm; ß+ + p to 132Nd (5/2+) N/A 1070.11 -
134Sm 133.93397(21)# 10(1) s ß+ to 134Pm 0+ N/A 1078.19 -
135Sm 134.93252(17) 10.3(5) s ß+ to 135Pm; ß+ + p to 134Nd (7/2+) N/A 1086.27 -
136Sm 135.928276(13) 47(2) s ß+ to 136Pm 0+ N/A 1103.67 -
137Sm 136.92697(5) 45(1) s ß+ to 137Pm (9/2-) N/A 1111.75 -
138Sm 137.923244(13) 3.1(2) min ß+ to 138Pm 0+ N/A 1119.82 -
139Sm 138.922297(12) 2.57(10) min ß+ to 139Pm 1/2+ N/A 1127.9 -
140Sm 139.918995(13) 14.82(12) min ß+ to 140Pm 0+ N/A 1145.3 -
141Sm 140.918476(9) 10.2(2) min ß+ to 141Pm 1/2+ N/A 1153.38 -
142Sm 141.915198(6) 72.49(5) min ß+ to 142Pm 0+ N/A 1161.46 -
143Sm 142.914628(4) 8.75(8) min ß+ to 143Pm 3/2+ N/A 1169.53 -
144Sm 143.911999(3) STABLE - 0+ N/A 1177.61 3.07
145Sm 144.913410(3) 340(3) d EC to 145Pm 7/2- -1.1 1185.69 -
146Sm 145.913041(4) 1.03(5)E+8 y a to 142Nd 0+ N/A 1193.77 -
147Sm 146.9148979(26) 1.06(2)E+11 y a to 143Nd 7/2- -0.8149 1201.85 14.99
148Sm 147.9148227(26) 7(3)E+15 y a to 144Nd 0+ N/A 1209.93 11.24
149Sm 148.9171847(26) STABLE - 7/2- -0.6718 1218.01 13.82
150Sm 149.9172755(26) STABLE - 0+ N/A 1226.08 7.38
151Sm 150.9199324(26) 90(8) y ß- to 151Eu 5/2- -0.363 1234.16 -
152Sm 151.9197324(27) STABLE - 0+ N/A 1242.24 26.75
153Sm 152.9220974(27) 46.284(4) h ß- to 153Eu 3/2+ -0.0216 1241 -
154Sm 153.9222093(27) STABLE - 0+ N/A 1249.08 22.75
155Sm 154.9246402(28) 22.3(2) min ß- to 155Eu 3/2- N/A 1257.16 -
156Sm 155.925528(10) 9.4(2) h ß- to 156Eu 0+ N/A 1265.24 -
157Sm 156.92836(5) 8.03(7) min ß- to 157Eu (3/2-) N/A 1273.32 -
158Sm 157.92999(8) 5.30(3) min ß- to 158Eu 0+ N/A 1281.4 -
159Sm 158.93321(11) 11.37(15) s ß- to 159Eu 5/2- N/A 1280.16 -
160Sm 159.93514(21)# 9.6(3) s ß- to 160Eu 0+ N/A 1288.24 -
161Sm 160.93883(32)# 4.8(8) s ß- to 161Eu 7/2+# N/A 1296.32 -
162Sm 161.94122(54)# 2.4(5) s ß- to 162Eu 0+ N/A 1295.08 -
163Sm 162.94536(75)# 1# s ß- to 163Eu 1/2-# N/A 1303.16 -
164Sm 163.94828(86)# 500# ms ß- to 164Eu 0+ N/A 1311.24 -
165Sm 164.95298(97)# 200# ms ß- to 165Eu 5/2-# N/A 1310 -