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About Terbium

Terbium Bohr

In 1787, army-lieutenant and chemist Carl Axel Arrhenius found a rock in a quarry near the Swedish village of Ytterby which he suspected contained the newly discovered element tungsten. Analysis by other chemists did not bear out his suspicions, but ultimately four new elements were identified from Arrhenius’s ytterbite. Carl Gustaf Mosander isolated three new oxides in 1843, one of which he named terbia, giving the corresponding element the name terbium.

A variety of terbium-doped compounds can act as phosphors for use in television screens, other displays, lighting, or sensors. Most notably, terbium green phosphors are used in trichromatic fluorescent lamps along with europium blue and red phosphors to produce white light with greater energy efficiency than incandescent lighting. In zirconia oxide ceramics, terbium can act both as a light-emitting dopant and a crystal stabilizer, producing a material with excellent structural and optical properties. Other terbium doped compounds have useful electrical properties that make them potentially useful in the semiconductor industry.

Terfenol-D is an alloy of terbium, iron, and dysprosium that is magnetostrictive: it contracts or expands when exposed to magnetic fields. This property allows direct conversion between electrical and mechanical power, and the alloy is used in sensors, actuators, and acoustic and ultrasonic transducers, and active noise and vibration cancelling devices. Terbium was also a component of gadolinium-terbium-iron thin films used in magneto-optical memory storage devices and specialized compact discs (CD-MO), but other forms of computer memory are currently preferred for most applications. Additionally, engineered terbium-binding peptides are being developed for use as sensitive optical biosensors for sensing enzymatic activity, and several radioactive terbium isotopes are being developed for medical applications as diagnostic tracers or cancer treatments.

Terbium is a rare earth element and can be found in any rare earth containing mineral, but as a heavy rare earth element (HREE) it is more common in HREE-enriched minerals such as xenotime and euxenite. Additionally, terbium is present in ion adsorption clays, which are a major source of HREEs due to their relative ease of processing, despite the low percentage quantities of rare earths they contain.


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Elemental Terbium Terbium is primarily used in phosphors, particularly in fluorescent lamps and as the high intensity green emitter used in projection televisions, such as the yttrium-aluminum-garnet (Tb:YAG) variety. Terbium alloys are also used in magneto-optic recording films, such as Tb-Fe-Co. Terbium 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. High Purity (99.999%) Terbium (Tb) Sputtering TargetTerbium nanoparticles and nanopowders provide ultra-high surface area which nanotechnology High Purity (99.999%) Terbium Oxide (Tb4O7) Powderresearch and recent experiments demonstrate function to create new and unique properties and benefits. Terbium oxide is 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. Terbium is also available in soluble forms including chlorides, nitrates and acetates. These compounds can be manufactured as solutions at specified stoichiometries.

Terbium Properties

Terbium Bohr ModelTerbium is a Block F, Group 3, Period 6 element. The number of electrons in each of Terbium's shells is 2, 8, 18, 27, 8, 2 and its electronic configuration is [Xe]4f9 6s2. The terbium atom has a radius of and its Van der Waals radius is In its elemental form, CAS 7440-27-9, terbium has a silvery-white appearance. Terbium was discovered and first isolated by Carl Gustaf Mosander in 1842. It is named after "Ytterby", the town in Sweden where it was discovered.

Symbol: Tb
Atomic Number: 65
Atomic Weight: 158.93
Element Category: Lanthanide
Group, Period, Block: n/a, 6, f
Color: silvery-gray/ silvery white
Other Names: Terbio, Térbio
Melting Point: 1356°C, 2472.8°F, 1629.15 K 
Boiling Point: 3230°C, 5846°F, 3503.15 K
Density: 8219 kg/m3
Liquid Density @ Melting Point: 7.65 g·cm3
Density @ 20°C: 8.27 g/cm3
Density of Solid: 8219 kg·m3
Specific Heat: 0.0437 Cal/g/K @ 25 °C
Superconductivity Temperature: N/A
Triple Point: N/A
Critical Point: N/A
Heat of Fusion (kJ·mol-1): 16.3
Heat of Vaporization (kJ·mol-1): 391
Heat of Atomization (kJ·mol-1): 390.62
Thermal Conductivity: 0.111 W/cm/K @ 298.2 K
Thermal Expansion: (r.t.) (poly) 10.3 µm/(m·K)
Electrical Resistivity: (r.t.) (poly) 1.150 nΩ·m
Tensile Strength: 60 MPa
Molar Heat Capacity: 28.91 J·mol-1·K-1
Young's Modulus: ( form) 55.7 GPa
Shear Modulus: ( form) 22.1 GPa
Bulk Modulus: ( form) 38.7 GPa
Poisson Ratio: ( form) 0.261
Mohs Hardness: N/A
Vickers Hardness: 863 MPa
Brinell Hardness: 677 MPa
Speed of Sound: (20 °C) 2620 m·s-1
Pauling Electronegativity: N/A
Sanderson Electronegativity: N/A
Allred Rochow Electronegativity: 1.1
Mulliken-Jaffe Electronegativity: N/A
Allen Electronegativity: N/A
Pauling Electropositivity: N/A
Reflectivity (%): N/A
Refractive Index: N/A
Electrons: 65
Protons: 65
Neutrons: 94
Electron Configuration: [Xe]4f9 6s2
Atomic Radius: 177 pm
Atomic Radius,
non-bonded (Å):
Covalent Radius: 194±5 pm
Covalent Radius (Å): 1.81
Van der Waals Radius: 221 pm
Oxidation States: 4, 3, 2, 1 (weakly basic oxide)
Phase: Solid
Crystal Structure: hexagonal close-packed
Magnetic Ordering: paramagnetic
Electron Affinity (kJ·mol-1) Unknown
1st Ionization Energy: 565.77 kJ·mol-1
2nd Ionization Energy: 1111.52 kJ·mol-1
3rd Ionization Energy: 2114.01 kJ·mol-1
CAS Number: 7440-27-9
EC Number: 231-137-6
MDL Number: MFCD00011256
Beilstein Number: N/A
SMILES Identifier: [Tb]
InChI Identifier: InChI=1S/Tb
PubChem CID: 23958
ChemSpider ID: 22397
Earth - Total: 54 ppb
Mercury - Total: 41 ppb
Venus - Total: 56 ppb 
Earth - Seawater (Oceans), ppb by weight: 0.00014
Earth - Seawater (Oceans), ppb by atoms: 0.000005
Earth -  Crust (Crustal Rocks), ppb by weight: 940
Earth -  Crust (Crustal Rocks), ppb by atoms: 120
Sun - Total, ppb by weight: 0.1
Sun - Total, ppb by atoms: 0.001
Stream, ppb by weight: 0.008
Stream, ppb by atoms: 0.0001
Meterorite (Carbonaceous), ppb by weight: 40
Meterorite (Carbonaceous), ppb by atoms: 5
Typical Human Body, ppb by weight: N/A
Typical Human Body, ppb by atom: N/A
Universe, ppb by weight: N/A
Universe, ppb by atom: N/A
Discovered By: Carl Gustaf Mosander
Discovery Date: 1842
First Isolation: N/A

Health, Safety & Transportation Information for Terbium

Terbium is considered to be somewhat toxic. Safety data for Terbium 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) Terbium.

Safety Data
Signal Word Danger
Hazard Statements H228
Hazard Codes F
Risk Codes 11
Safety Precautions N/A
RTECS Number N/A
Transport Information N/A
WGK Germany 3
Globally Harmonized System of
Classification and Labelling (GHS)
Review and Print SDS for Terbium Metal


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


Product Name: Terbium Metal

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

CAS #: 7440-27-9

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 in accordance with 29 CFR 1910 (OSHA HCS)
The substance is not classified according to the Globally Harmonized System (GHS).
Hazards not otherwise classified
No information known.
Label elements
GHS label elements
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) = 0
Flammability = 0
Physical Hazard = 0
Other hazards
Results of PBT and vPvB assessment
Not applicable.
Not applicable.


Chemical characterization: Substances
CAS# Description:
7440-27-9 Terbium
Identification number(s):
EC number:


Description of first aid measures
After inhalation
Supply fresh air. If required, provide artificial respiration. Keep patient warm.
Seek immediate medical advice.
After skin contact
Immediately wash with water and soap and rinse thoroughly.
Seek immediate medical advice.
After eye contact
Rinse opened eye for several minutes under running water. Then consult a doctor.
After swallowing
Seek medical treatment.
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
CO2, sand, extinguishing powder. Do not use water.
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:
Wear self-contained respirator.
Wear fully protective impervious suit.


Personal precautions, protective equipment and emergency procedures
Wear protective equipment. Keep unprotected persons away.
Ensure adequate ventilation
Environmental precautions:
Do not allow material to be released to the environment without proper governmental permits.
Methods and material for containment and cleaning up:
Dispose of the collected material according to regulations.
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
Keep container tightly sealed.
Store in cool, dry place in tightly closed containers.
Information about protection against explosions and fires:
No information known.
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 halogens.
Further information about storage conditions:
Keep container tightly sealed.
Store in cool, dry conditions in well sealed containers.
Specific end use(s)
No further relevant information available.


Additional information about design of technical systems:
Properly operating chemical fume hood designed for hazardous chemicals and having an average face velocity of at least 100 feet per minute.
Control parameters
Components with limit values that require monitoring at the workplace:
Not required.
Additional information:
No data
Exposure controls
Personal protective equipment
General protective and hygienic measures
The usual precautionary measures for handling chemicals should be followed.
Keep away from foodstuffs, beverages and feed.
Remove all soiled and contaminated clothing immediately.
Wash hands before breaks and at the end of work.
Maintain an ergonomically appropriate working environment.
Breathing equipment:
Use suitable respirator when high concentrations are present.
Protection of hands:
Impervious gloves
Check protective gloves prior to each use for their proper condition.
The selection of suitable gloves not only depends on the material, but also on quality. Quality will vary from manufacturer to manufacturer.
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: Not determined
Odor threshold: Not determined.
pH-value: Not determined.
Change in condition
Melting point/Melting range: 1356 °C (2473 °F)
Boiling point/Boiling range: 2800 °C (5072 °F)
Sublimation temperature / start: Not determined
Flash point: Not applicable
Flammability (solid, gaseous)
Fine powder: highly flammable
Ignition temperature: Not determined
Decomposition temperature: Not determined
Auto igniting: Not determined.
Danger of explosion: Product does not present an explosion hazard.
Explosion limits:
Lower: Not determined
Upper: Not determined
Vapor pressure at 20 °C (68 °F): 0 hPa
Density at 20 °C (68 °F): 8.27 g/cm³ (69.013 lbs/gal)
Relative density
Not determined.
Vapor density
Not determined.
Evaporation rate
Not applicable.
Solubility in / Miscibility with Water: Not miscible or difficult to mix
Partition coefficient (n-octanol/water): Not determined.
dynamic: Not determined.
kinematic: Not determined.
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:
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:
Lanthanons can cause delayed blood clotting leading to hemorrhages.
Exposure may also lead to sensitivity to heat, itching, increased awareness of odor and taste,
and liver damage.
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 a hazardous material for transportation.
UN proper shipping name
Transport hazard class(es)
Packing group
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:
Not dangerous according to the above specifications.
Marine Pollutant (DOT):


Safety, health and environmental regulations/legislation specific for the substance or mixture
GHS label elements
Not applicable
Hazard pictograms
Not applicable
Signal word
Not applicable
Hazard statements
Not applicable
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 Non-Domestic Substances List (NDSL).
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.
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.

Terbium Isotopes

Naturally occurring terbium (Tb) has one stable isotope: 159Tb

Nuclide Isotopic Mass Half-Life Mode of Decay Nuclear Spin Magnetic Moment Binding Energy (MeV) Natural Abundance
(% by atom)
135Tb 135 0.94(+33-22) ms Unknown (7/2-) N/A N/A -
136Tb 135.96138(64)# 0.2# s Unknown N/A N/A 1063.04 -
137Tb 136.95598(64)# 600# ms Unknown 11/2-# N/A 1080.43 -
138Tb 137.95316(43)# 800# ms [>200 ns] ß+ to 138Gd; p to 137Gd N/A N/A 1088.51 -
139Tb 138.94829(32)# 1.6(2) s ß+ to 139Gd; ß+ + p to 139Eu 11/2-# N/A 1105.9 -
140Tb 139.94581(86) 2.4(2) s ß+ to 140Gd 5 N/A 1113.98 -
141Tb 140.94145(11) 3.5(2) s ß+ to 141Gd (5/2-) N/A 1122.06 -
142Tb 141.93874(32)# 597(17) ms ß+ to 142Gd; ß+ + p to 141Eu 1+ N/A 1139.46 -
143Tb 142.93512(6) 12(1) s ß+ to 143Gd (11/2-) N/A 1147.54 -
144Tb 143.93305(3) ~1 s ß+ to 144Gd 1+ N/A 1155.61 -
145Tb 144.92927(6) 20# min ß+ to 145Gd (3/2+) N/A 1173.01 -
146Tb 145.92725(5) 8(4) s ß+ to 146Gd 1+ N/A 1181.09 -
147Tb 146.924045(13) 1.64(3) h ß+ to 147Gd 1/2+# N/A 1189.17 -
148Tb 147.924272(15) 60(1) min ß+ to 148Gd 2- N/A 1197.25 -
149Tb 148.923246(5) 4.118(25) h ß+ to 149Gd; a to 145Eu 1/2+ N/A 1205.32 -
150Tb 149.923660(8) 3.48(16) h ß+ to 150Gd; a to 146Eu (2-) N/A 1213.4 -
151Tb 150.923103(5) 17.609(1) h ß+ to 151Gd; a to 147Eu 1/2(+) N/A 1221.48 -
152Tb 151.92407(4) 17.5(1) h ß+ to 152Gd; a to 148Eu 2- N/A 1229.56 -
153Tb 152.923435(5) 2.34(1) d EC to 153Gd 5/2+ 3.5 1237.64 -
154Tb 153.92468(5) 21.5(4) h EC to 154Gd; ß- to 154Dy 0(+#) 0.9 1245.72 -
155Tb 154.923505(13) 5.32(6) d EC to 155Gd 3/2+ 2 1253.8 -
156Tb 155.924747(5) 5.35(10) d EC to 156Gd; ß- to 156Dy 3- 1.4 1261.87 -
157Tb 156.9240246(27) 71(7) y EC to 157Gd 3/2+ 2 1269.95 -
158Tb 157.9254131(28) 180(11) y EC to 158Gd; ß- to 158Dy 3- 1.76 1278.03 -
159Tb 158.9253468(27) STABLE - 3/2+ 2.014 1286.11 100
160Tb 159.9271676(27) 72.3(2) d ß- to 160Dy 3- 1.79 1294.19 -
161Tb 160.9275699(28) 6.906(19) d ß- to 161Dy 3/2+ 2.2 1302.27 -
162Tb 161.92949(4) 7.60(15) min ß- to 162Dy 1- N/A 1310.35 -
163Tb 162.930648(5) 19.5(3) min ß- to 163Dy 3/2+ N/A 1309.11 -
164Tb 163.93335(11) 3.0(1) min ß- to 164Dy (5+) N/A 1317.19 -
165Tb 164.93488(21)# 2.11(10) min ß- to 165Dy 3/2+# N/A 1325.27 -
166Tb 165.93799(11) 25.6(22) s ß- to 166Dy N/A N/A 1333.35 -
167Tb 166.94005(43)# 19.4(27) s ß- to 167Dy 3/2+# N/A 1332.11 -
168Tb 167.94364(54)# 8.2(13) s ß- to 168Dy 4-# N/A 1340.19 -
169Tb 168.94622(64)# 2# s ß- to 169Dy 3/2+# N/A 1348.27 -
170Tb 169.95025(75)# 3# s ß- to 170Dy N/A N/A 1347.03 -
171Tb 170.95330(86)# 500# ms ß- to 171Dy 3/2+# N/A 1355.11 -