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About Rhenium

Rhenium Bohr

By the early twentieth century, what we know as the modern periodic table had largely taken shape. For the most part, what chemical discoveries remained would require the use of nuclear reactors rather than the traditional chemist’s patient examination and chemical analysis of unusual ores. There were, however, a few remaining holes in the table outside of the bottom rows that would later come to be filled with lab-produced radioactive elements; two of these missing elements were numbers 43 and 75.

Both of these elements had been predicted by Mendeleev, who had named them ekamanganese and dwimanganese respectively, but despite many attempts and declarations of discovery later deemed false, both elements remained elusive until 1924. In that year, the team of Walter Noddack and Ida Tacke, two German chemists who later married, with the assistance of Otto Berg, believed that they had found both of these missing elements in platinum ores, an assertion they based on spectral data. They named element 43 “masurian” for Noddack’s birthplace in the masurian marshes district, and element 75 “rhenium” from Tacke’s birthplace in Rhenany-Rhineland. Unfortunately, the team was only able to actually isolate substantial quantities of rhenium, and later theories convinced the scientific community that in fact, element 43 would be too unstable to be found by natural means. This lead to widespread disrespect for Tacke and Noddack as scientists, despite their verified discovery of one of the missing elements.

The early extraction and purification process for the rare element rhenium was complicated and expensive, which long delayed its industrial use. Even today, its applications are limited by its low availability, and is used primarily in functions where small quantities can provide substantial benefits. One of these functions is as an alloy additive: rhenium is a component of many heat-resistant superalloys. Nickel-based superalloys are frequently used in jet engines, where they are valued for high resistance to creep. Tungsten-rhenium and molybdenum-rhenium are used in thermocouples most often deployed for sensing extremely high temperatures. Rhenium-containing alloys may also find use in crucibles, self-cleaning electrical contacts, electromagnets, ionization gauges, and mass spectrographs. The other major use of rhenium is as a catalyst; it serves this function in the processing of petroleum, alongside platinum in catalytic converters, and in a number of niche or still developing applications. Additionally, Re-188 and Re-186 are used in cancer radiotherapy.

Rhenium is most often found in small quantities in molybdenum deposits, and is obtained through processing of molybdenum concentrates. Additionally, platinum-rhenium catalysts and rhenium alloy scrap are frequently recycled.


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High-temperature rhenium super-alloys are used to make jet engine parts. Platinum-rhenium catalysts are used in lead-free, high-octane, gasoline. Rhenium is also used as a filament for mass spectrographs and ion gauges. Because rhenium has good wear resistance and withstands arc corrosion, it is used as an electrical High Purity (99.999%) Rhenium (Re) Sputtering Targetcontact material. Thermocouples made of Re-W are used for measuring temperatures up to 2200C, and rhenium wire is used in photographic flash lamps. Rhenium is available as metal and compounds with purities from 99% to 99.999% (ACS grade to ultra-high purity). High Purity (99.999%) Rhenium Oxide (ReO2) PowderElemental or metallic forms include pellets, rod, wire and granules for evaporation source material purposes. Rhenium nanoparticles and nanopowders provide ultra-high surface area. Rhenium oxides are available in powder and dense pellet form for such uses as optical coating and thin film applications. Oxides tend to be insoluble. Rhenium 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. Rhenium is also available in soluble forms including as its chlorides. These compounds can be manufactured as solutions at specified stoichiometries.

Rhenium Properties

Rhenium(Re) atomic and molecular weight, atomic number and elemental symbolRhenium is a Block D, Group 7, Period 6 element. The number of electrons in each of rhenium's shells is 2, 8, 18, 32, 13, 2 and its electron configuration is [Xe] 4f14 5d5 6s2. Rhenium Bohr Model

Symbol: Re
Atomic Number: 75
Atomic Weight: 186.207
Element Category: transition metal
Group, Period, Block: 7, 6, d
Color: grayish white/ silvery-white
Other Names: Rhénium, Renio, Rênio
Melting Point: 3186 °C, 5767 °F, 3459 K
Boiling Point: 5596 °C, 10105 °F, 5869 K
Density: 21.02 g·cm3
Liquid Density @ Melting Point: 18.9 g·cm3
Density @ 20°C: 21.0 g/cm3
Density of Solid: 21020 kg·m3
Specific Heat: 0.14 (kJ/kg K)
Superconductivity Temperature: 1.70 [or -271.4 °C (-456.5 °F)] K
Triple Point: N/A
Critical Point: N/A
Heat of Fusion (kJ·mol-1): 33.1
Heat of Vaporization (kJ·mol-1): 704.25
Heat of Atomization (kJ·mol-1): 769
Thermal Conductivity: 48.0 W·m-1·K-1
Thermal Expansion: 6.2 µm/(m·K)
Electrical Resistivity: (20 °C) 193 nΩ·m
Tensile Strength: N/A
Molar Heat Capacity: 25.48 J·mol-1·K-1
Young's Modulus: 463 GPa
Shear Modulus: 178 GPa
Bulk Modulus: 370 GPa
Poisson Ratio: 0.3
Mohs Hardness: 7
Vickers Hardness: 2450 MPa
Brinell Hardness: 1320 MPa
Speed of Sound: (20 °C) 4700 m·s-1
Pauling Electronegativity: 1.9
Sanderson Electronegativity: N/A
Allred Rochow Electronegativity: 1.46
Mulliken-Jaffe Electronegativity: N/A
Allen Electronegativity: N/A
Pauling Electropositivity: 2.1
Reflectivity (%): N/A
Refractive Index: N/A
Electrons: 75
Protons: 75
Neutrons: 111
Electron Configuration: [Xe] 4f14 5d5 6s2
Atomic Radius: 137 pm
Atomic Radius,
non-bonded (Å):
Covalent Radius: 151±7 pm
Covalent Radius (Å): 1.41
Van der Waals Radius: 200 pm
Oxidation States: 7, 6, 5, 4, 3, 2, 1, 0, -1 (mildly acidic oxide)
Phase: Solid
Crystal Structure: hexagonal close-packed
Magnetic Ordering: paramagnetic
Electron Affinity (kJ·mol-1) 14.468
1st Ionization Energy: 760 kJ·mol-1
2nd Ionization Energy: 1260 kJ·mol-1
3rd Ionization Energy: 2510 kJ·mol-1
CAS Number: 7440-15-5
EC Number: 231-124-5
MDL Number: MFCD00011195
Beilstein Number: N/A
SMILES Identifier: [Re]
InChI Identifier: InChI=1S/Re
PubChem CID: 23947
ChemSpider ID: 22388
Earth - Total: 60 ppb
Mercury - Total: 46 ppb
Venus - Total: 64 ppb
Earth - Seawater (Oceans), ppb by weight: 0.001
Earth - Seawater (Oceans), ppb by atoms: 0.000033
Earth -  Crust (Crustal Rocks), ppb by weight: 2.6
Earth -  Crust (Crustal Rocks), ppb by atoms: 0.3
Sun - Total, ppb by weight: 0.1
Sun - Total, ppb by atoms: 0.0005
Stream, ppb by weight: N/A
Stream, ppb by atoms: N/A
Meterorite (Carbonaceous), ppb by weight: 50
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: 0.2
Universe, ppb by atom: 0.001
Discovered By: Masataka Ogawa
Discovery Date: 1908
First Isolation: Masataka Ogawa (1908)

Health, Safety & Transportation Information for Rhenium

Very little is known about the toxicity of rhenium and its compounds. Safety data for Rhenium 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) Rhenium.

Safety Data
Signal Word Danger
Hazard Statements H228
Hazard Codes F
Risk Codes 11
Safety Precautions 16
RTECS Number VI0780000
Transport Information N/A
WGK Germany nwg
Globally Harmonized System of
Classification and Labelling (GHS)
Review and Print SDS for Rhenium Metal


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


Product Name: Rhenium Metal

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

CAS #: 7440-15-5

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.
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) = 0
Flammability = 0
Physical Hazard = 0
Other hazards
Results of PBT and vPvB assessment
Not applicable.
Not applicable.


Chemical characterization: Substances
CAS# Description:
7440-15-5 Rhenium
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.
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
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:
Not required.
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:
No further data; see section 7.
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.
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: 3180 °C (5756 °F)
Boiling point/Boiling range: 5900 °C (10652 °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: Product does not present an explosion hazard.
Explosion limits:
Lower: Not determined
Upper: Not determined
Vapor pressure: Not applicable.
Density at 20 °C (68 °F): 21.04 g/cm³ (175.579 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:
No information known.
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:
Powder: irritant effect
Eye irritation or corrosion:
Powder: 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.
Carcinogenic categories
OSHA-Ca (Occupational Safety & Health Administration)
Substance is not listed


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
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.
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.

Rhenium Isotopes

Naturally occurring rhenium (Re) has two isotopes: 185Re (37.4%) and 187Re (62.6%) .

Nuclide Isotopic Mass Half-Life Mode of Decay Nuclear Spin Magnetic Moment Binding Energy (MeV) Natural Abundance
(% by atom)
160Re 159.98212(43)# 860(120) µs [0.82(+15-9) ms] p to 159W; a to 156Ta (2-) N/A 1227.07 -
161Re 160.97759(22) 0.37(4) ms p to 160W 1/2+ N/A 1244.47 -
162Re 161.97600(22)# 107(13) ms a to 158Ta; ß+ to 162W (2-) N/A 1252.54 -
163Re 162.972081(21) 390(70) ms ß+ to 163W; a to 159Ta (1/2+) N/A 1260.62 -
164Re 163.97032(17)# 0.53(23) s a to 160Ta; ß+ to 164W high N/A 1268.7 -
165Re 164.967089(30) 1# s ß+ to 165W; a to 161Ta 1/2+# N/A 1286.1 -
166Re 165.96581(9)# 2# s ß+ to 166W; a to 162Ta 2-# N/A 1294.18 -
167Re 166.96260(6)# 3.4(4) s a to 163Ta; ß+ to 167W 9/2-# N/A 1302.25 -
168Re 167.96157(3) 4.4(1) s ß+ to 168W; a to 164Ta (5+,6+,7+) N/A 1310.33 -
169Re 168.95879(3) 8.1(5) s ß+ to 169W; a to 165Ta 9/2-# N/A 1327.73 -
170Re 169.958220(28) 9.2(2) s ß+ to 170W; a to 166Ta (5+) N/A 1335.81 -
171Re 170.95572(3) 15.2(4) s ß+ to 171W (9/2-) N/A 1343.89 -
172Re 171.95542(6) 15(3) s ß+ to 172W -5 N/A 1351.96 -
173Re 172.95324(3) 1.98(26) min ß+ to 173W (5/2-) N/A 1360.04 -
174Re 173.95312(3) 2.40(4) min ß+ to 174W N/A N/A 1368.12 -
175Re 174.95138(3) 5.89(5) min ß+ to 175W (5/2-) N/A 1376.2 -
176Re 175.95162(3) 5.3(3) min ß+ to 176W 3+ N/A 1384.28 -
177Re 176.95033(3) 14(1) min ß+ to 177W 5/2- N/A 1392.36 -
178Re 177.95099(3) 13.2(2) min ß+ to 178W (3+) N/A 1400.44 -
179Re 178.949988(26) 19.5(1) min ß+ to 179W (5/2)+ N/A 1417.83 -
180Re 179.950789(23) 2.44(6) min ß+ to 180W (1)- N/A 1416.59 -
181Re 180.950068(14) 19.9(7) h ß+ to 181W 5/2+ N/A 1424.67 -
182Re 181.95121(11) 64.0(5) h EC to 182W 7+ 2.8 1432.75 -
183Re 182.950820(9) 70.0(14) d EC to 183W 5/2+ 3.17 1440.83 -
184Re 183.952521(5) 38.0(5) d EC to 184W 3(-) 2.53 1448.91 -
185Re 184.9529550(13) Observationally Stable - 5/2+ 3.1871 1456.99 37.4
186Re 185.9549861(13) 3.7186(5) d EC to 186W; ß- to 186Os 1- 1.739 1465.07 -
187Re 186.9557531(15) 41.2(2)E+9 y ß- to 187Os; a to 183Ta 5/2+ 3.2197 1473.15 62.6
188Re 187.9581144(15) 17.0040(22) h ß- to 188Os 1- 1.788 1481.22 -
189Re 188.959229(9) 24.3(4) h ß- to 189Os 5/2+ N/A 1489.3 -
190Re 189.96182(16) 3.1(3) min ß- to 190Os (2)- N/A 1488.06 -
191Re 190.963125(11) 9.8(5) min ß- to 191Os (3/2+,1/2+) N/A 1496.14 -
192Re 191.96596(21)# 16(1) s ß- to 192Os N/A N/A 1504.22 -
193Re 192.96747(21)# 30# s [>300 ns] Unknown 5/2+# N/A 1512.3 -
194Re 193.97042(32)# 2# s [>300 ns] Unknown N/A N/A 1511.06 -