Technetium (Tc)
transition-metalSolid
Standard Atomic Weight
[98]Electron configuration
[Kr] 5s2 4d5Melting point
2156.85 °CBoiling point
4264.85 °CDensity
1.1e+4 kg/m³Oxidation states
−3, −1, +1, +2, +3, +4, +5, +6, +7Electronegativity (Pauling)
1.9Ionization energy (1st)
7.11938 eVDiscovery year
1937Atomic radius
135 pmDetails
Technetium is a radioactive transition metal in group 7, between molybdenum and ruthenium. It was the first element discovered without a stable isotope. Only trace natural technetium occurs, mainly from spontaneous fission of uranium and from neutron capture processes; practical quantities are made artificially. Its chemistry resembles rhenium and manganese in several oxidation states, and the isotope ⁹⁹ᵐTc is central to diagnostic nuclear medicine.
Technetium is a silvery-gray metal that tarnishes slowly in moist air. The common oxidation states of technetium are +7, +5, and +4. Under oxidizing conditions technetium (VII) will exist as the pertechnetate ion, TcO4-. The chemistry of technetium is said to be similar to that of rhenium. Technetium dissolves in nitric acid, aqua regia, and concentrated sulfuric acid, but is not soluble in hydrochloric acid of any strength. The element is a remarkable corrosion inhibitor for steel. The metal is an excellent superconductor at 11K and below.
Technetium was the first artificially produced element. It was isolated by Carlo Perrier and Emilio Segrè in 1937. Technetium was created by bombarding molybdenum atoms with deuterons that had been accelerated by a device called a cyclotron. Today, technetium is produced by bombarding molybdenum-98 with neutrons. Molybdenum-98 becomes molybdenum-99 when it captures a neutron. Molybdenum-99, with a half-life of 65.94 hours, decays into technetium-99 through beta decay. While technetium has never been found to occur naturally on earth, its spectral lines have been observed in S-, M- and N-type stars.
Technetium's most stable isotope, technetium-98, has a half-life of about 4,200,000 years. It decays into ruthenium-98 through beta decay.
From the Greek word technetos, artificial. Element 43 was predicted on the basis of the periodic table, and was erroneously reported as having been discovered in 1925, at which time it was named masurium. The element was actually discovered by Perrier and Segre in Italy in 1937. It was also found in a sample of molybdenum sent by E. Lawrence that was bombarded by deuterons in the Berkeley cyclotron. Technetium was the first element to be produced artificially. Since its discovery, searches for the element in terrestrial material have been made. Finally in 1962, technetium-99 was isolated and identified in African pitchblende (a uranium rich ore) in extremely minute quantities as a spontaneous fission product of uranium-238 by B.T. Kenna and P.K. Kuroda. If it does exist, the concentration must be very small. Technetium has been found in the spectrum of S-, M-, and N-type stars, and its presence in stellar matter is leading to new theories of the production of heavy elements in the stars.
Macroscopic technetium metal is a silvery-gray, metallic solid when prepared in the laboratory. Because all isotopes are radioactive, specimens are handled as controlled radioactive materials rather than ordinary metal samples.
The most important use is isotope-specific: ⁹⁹ᵐTc is used as a short-lived gamma-emitting tracer in many diagnostic imaging procedures, usually bound in radiopharmaceutical complexes selected for particular organs or physiological processes. Longer-lived ⁹⁹Tc has been studied as a corrosion inhibitor for steel in closed systems, but its radioactivity and regulatory burden prevent ordinary industrial use. Other technetium isotopes and compounds are used mainly in chemical, nuclear, and tracer research.
Small amounts of technetium can retard the corrosion of steel, although this protection can only be applied to closed systems due to technetium's radioactivity. Technetium can also be used as a medical tracer and to calibrate particle detectors.
Isotopes in Medicine
99mTc is an isomer of 99Tc with a half-life of approximately 6 h that is used to label peptides for morphologic (the form and structure of an organism) and dynamic modeling of renal (kidney), hepatic (liver), bone, and cardiac imaging [320] U. Abram, R. Alberto. J. Braz. Chem. Soc.17, 1486 (2006)., [322] M. Pérez Díaz, J. Quevedo Garcia, O. Diaz Rizo, R. Dopico Hernandez, E. Estevez Aparicio, A. Viamonte Marin, O. Cabrera Gorrin. Alasbimn J.4 (16), (2002).. 99mTc radiopharmaceuticals absorb to a variety of tumors. These tumors can be imaged using single-photon emission computed tomography (SPECT) coupled with non-invasive computed tomography (CT scan), which provides a high level of functional and anatomical information in a three-dimensional image (Fig. IUPAC.43.1) [323] A. Ballard. Biomarkers Key to Drug Development: Imaging and Biomarkers Drive Drug Development Engineered for Personalized Medicine, Imaging Technology News (2014), Feb. 26; http://www.itnonline.com/article/biomarkers-key-drug-development., [324] P. Ghosh, M. Kelly. Expanding the Power of PET with 18F-Sodium Fluoride, Siemens Medical Solutions USA, Inc (2017), Feb. 26; https://usa.healthcare.siemens.com/siemens_hwem-hwem_ssxa_websites-context-root/wcm/idc/groups/public/@us/@imaging/@molecular/documents/mdaw/ndu0/∼edisp/white_paper10_sodium_fluoride-00309726.. Medronate is a radioactive pharmaceutical, which has been used to find, treat, or study certain diseases or body functions. 99mTc-labeled medronate (99mTc-MDP) is used in a diagnostic test to detect metastases from prostate, lung or thyroid cancer, making use of a gamma camera to record the distribution of 99mTc-MDP within the body. A two-dimensional image of the affected areas is produced.
Technetium shows rich redox chemistry, with common oxidation states including +7, +4, and lower states in coordination complexes. Pertechnetate, TcO₄⁻, contains technetium(VII) and is chemically analogous to perrhenate; sodium pertechnetate, NaTcO₄, is a key soluble form in radiochemistry. Technetium dioxide, TcO₂, contains technetium(IV) and is much less mobile in many reducing environments. Technetium forms halides, oxides, sulfides, and numerous complexes with phosphines, carbonyls, and biological ligands.
See more information at the Technetium compound page.
All technetium isotopes are radioactive, but hazards differ strongly by isotope, activity, chemical form, and route of exposure. ⁹⁹ᵐTc has a short half-life and is managed under medical radiation controls. ⁹⁹Tc is a long-lived beta emitter; ingestion or inhalation of soluble pertechnetate is a principal concern because it can distribute in body fluids. Metal dusts and contaminated laboratory surfaces require radiological containment and monitoring.
It is reported that mild carbon steels may be effectively protected by as little as 55 ppm of KTcO4 in aerated distilled water at temperatures up to 250°C. This corrosion protection is limited to closed systems, since technetium is radioative and must be confined. 98Tc has a specific activity of 6.2 x 108 Bq/g. Activity of this level must not be allowed to spread. 99Tc is a contamination hazard and should be handled in a glove box.
Natural technetium is extremely scarce and transient on geological scales. Environmental technetium of practical concern comes mainly from nuclear fission products in reactor fuel, reprocessing streams, waste, and fallout residues. Pertechnetate, TcO₄⁻, is soluble and relatively mobile under oxidizing conditions, while reduced technetium(IV) species such as TcO₂ are less soluble and can be retained by sediments or engineered waste forms.
Technetium has no normal commodity market as a bulk metal. Supply is tied to the nuclear industry and to isotope generation. Medical ⁹⁹ᵐTc is obtained from decay of ⁹⁹Mo in generator systems, with ⁹⁹Mo produced mainly by fission or neutron-activation routes. Long-lived ⁹⁹Tc is available as a fission product recovered in specialized facilities, but demand is limited by regulation and by its lack of ordinary commercial applications. Costs are dominated by reactor or accelerator production, radiochemical processing, transport timing, quality control, and waste management rather than by the elemental metal itself.
Made first by bombarding molybdenum with deuterons (heavy hydrogen) in a cyclotron.
Technetium has no stable nuclides, so any primordial technetium has decayed away. It is produced in stars by neutron-capture nucleosynthesis, and its spectroscopic detection in some red giant stars shows that freshly made heavy elements can be brought to stellar surfaces. In planetary materials it is expected only in trace radiogenic or cosmogenic amounts unless introduced by nuclear processes.
- Technetium was identified in molybdenum targets irradiated with deuterons.
- Its name comes from a Greek word meaning artificial.
- The diagnostic isotope ⁹⁹ᵐTc decays to ⁹⁹Tc.
- Pertechnetate, TcO₄⁻, is often the most mobile oxidized form in water.
- A visible technetium spectrum in a star proved that some stellar heavy elements are made recently.
Images
Properties
Physical
- Atomic radius (empirical)
- 135 pm Compare Atomic radius (empirical) of all elements →
- Covalent radius
- 147 pm Compare Covalent radius of all elements →
- Van der Waals radius
- 209 pm Compare Van der Waals radius of all elements →
- Metallic radius
- 127 pm Compare Metallic radius of all elements →
- Density
- 1.1 × 104 kg/m³ Compare Density of all elements →
- Molar volume
- 0.0085 L/mol
- Phase at STP
- Solid Compare Phase at STP of all elements →
- Melting point
- 2156.85 °C Compare Melting point of all elements →
- Boiling point
- 4264.85 °C Compare Boiling point of all elements →
- Thermal conductivity
- 50.6 W/(m·K) Compare Thermal conductivity of all elements →
- Crystal structure
- Hexagonal close-packed Compare Crystal structure of all elements →
Chemical
- Electronegativity (Pauling)
- 1.9 Compare Electronegativity (Pauling) of all elements →
- Electronegativity (Allen)
- 1.51
- Electron affinity
- 0.55 eV
- Ionization energy (1st)
- 7.11938 eV Compare Ionization energy (1st) of all elements →
- Ionization energy (2nd)
- 15.260053 eV Compare Ionization energy (2nd) of all elements →
- Ionization energy (3rd)
- 29.550102 eV Compare Ionization energy (3rd) of all elements →
- Ionization energy (4th)
- 41.000141 eV Compare Ionization energy (4th) of all elements →
- Ionization energy (5th)
- 57.000196 eV Compare Ionization energy (5th) of all elements →
- Oxidation states
- −3, −1, +1, +2, +3, +4, +5, +6, +7 Compare Oxidation states of all elements →
- Valence electrons
- 7 Compare Valence electrons of all elements →
- Electron configuration
- [Kr] 5s2 4d5
Thermodynamic
- Heat of fusion
- 0.24667047 eV Compare Heat of fusion of all elements →
- Heat of vaporization
- 5.182153 eV Compare Heat of vaporization of all elements →
- Heat of sublimation
- 6.063119 eV
- Heat of atomization
- 6.063119 eV
- Atomization enthalpy
- 7.026999 eV
Nuclear
- Protons
- 43 Compare Protons of all elements →
- Neutrons
- 55 Compare Neutrons of all elements →
- Known isotopes
- 40 Compare Known isotopes of all elements →
- Stable isotopes
- 0 Compare Stable isotopes of all elements →
- Mass number (most stable)
- 98
- Most stable isotope
- Tc-98
- Discovery year
- 1937
Abundance
N/A
Crystal Structure
- Lattice constant a
- 274 pm
Electronic Structure
- Electrons per shell
- 2, 8, 18, 13, 2 Compare Electrons per shell of all elements →
Identifiers
- CAS number
- 7440-26-8 Compare CAS number of all elements →
- Term symbol
- 6S5/2
- InChI
- InChI=1S/Tc
- InChI Key
- GKLVYJBZJHMRIY-UHFFFAOYSA-N
Electron Configuration Measured
Tc: 4d⁵ 5s²[Kr] 4d⁵ 5s²1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d⁵ 5s²Atomic model
Isotopes change neutron count, mass, and stability — not the electron configuration of a neutral atom.
Schematic atomic model, not to scale.
Atomic Fingerprint
Emission / Absorption Spectrum
Isotope Distribution
No stable isotopes.
| Mass number | Atomic mass (u) | Natural abundance | Half-life |
|---|---|---|---|
| 109 Radioactive | 108.920256 ± 0.00001 | N/A | 905 ms |
| 110 Radioactive | 109.923744 ± 0.00001 | N/A | 900 ms |
| 111 Radioactive | 110.925901 ± 0.000011 | N/A | 350 ms |
| 112 Radioactive | 111.9299458 ± 0.000006 | N/A | 323 ms |
| 94 Radioactive | 93.9096536 ± 0.0000044 | N/A | 293 minutes |
Phase / State
Reason: 2131.8 °C below melting point (2156.85 °C)
Schematic, not to scale
Phase transition points
Transition energies
Energy required to melt 1 mol at melting point
Energy required to vaporize 1 mol at boiling point
Energy required to sublime 1 mol at sublimation point
Density
At standard conditions
At standard conditions
Atomic Spectra
Showing 10 of 43. Sorted by ion charge (ascending).
Lines Holdings ?
| Ion | Charge | Total lines | Transition probabilities | Level designations |
|---|---|---|---|---|
| Tc I | 0 | 600 | 13 | 561 |
| Tc II | +1 | 40 | 6 | 23 |
Levels Holdings ?
| Ion | Charge | Levels |
|---|---|---|
| Tc I | 0 | 290 |
| Tc II | +1 | 34 |
| Tc III | +2 | 2 |
| Tc IV | +3 | 2 |
| Tc V | +4 | 2 |
| Tc VI | +5 | 2 |
| Tc VII | +6 | 2 |
| Tc VIII | +7 | 2 |
| Tc IX | +8 | 2 |
| Tc X | +9 | 2 |
Ionic Radii
| Charge | Coordination | Spin | Radius |
|---|---|---|---|
| +4 | 6 | N/A | 64.5 pm |
| +5 | 6 | N/A | 60 pm |
| +7 | 4 | N/A | 37 pm |
| +7 | 6 | N/A | 56.00000000000001 pm |
Compounds
Isotopes (5)
Twenty-two isotopes of technetium with masses ranging from 90 to 111 are reported. All the isotopes of technetium are radioactive. It is one of two elements with Z < 83 that have no stable isotopes; the other element is promethium (Z = 61). Technetium has three long lived radioactive isotopes: 97Tc (T1/2 = 2.6 x 106 years), 98Tc (T1/2 = 4.2 x 106 years) and 99Tc (T1/2 = 2.1 x 105 years). 95Tcm ("m" stands for meta state) (T1/2 = 61 days) is used in tracer work. However, the most useful isotope of technetium is 99Tcm (T1/2 = 6.01 hours) is used in many medical radioactive isotope tests because of its half-life being short, the energy of the gamma ray it emits, and the ability of technetium to be chemically bound to many biologically active molecules. Because 99Tc is produced as a fission product from the fission of uranium in nuclear reactors, large quantities have been produced over the years. There are kilogram quantities of technetium currently existing.
| Mass number | Atomic mass (u) | Natural abundance | Half-life | Decay mode | |
|---|---|---|---|---|---|
| 109 Radioactive | 108.920256 ± 0.00001 | N/A | 905 ms | β- =100%β-n =0.08±0.2% | |
| 110 Radioactive | 109.923744 ± 0.00001 | N/A | 900 ms | β- =100%β-n =0.04±0.2% | |
| 111 Radioactive | 110.925901 ± 0.000011 | N/A | 350 ms | β- =100%β-n =0.85±2% | |
| 112 Radioactive | 111.9299458 ± 0.000006 | N/A | 323 ms | β- =100%β-n =1.5±0.2% | |
| 94 Radioactive | 93.9096536 ± 0.0000044 | N/A | 293 minutes | β+ =100% |
Spectral Lines
Showing 50 of 277. Only spectral lines with measured intensity are shown by default.
| Wavelength (nm) | Intensity | Ion stage | Type | Transition | Accuracy | Source | |
|---|---|---|---|---|---|---|---|
| 485.359 nm | 20000 | Tc I | emission | 4d6.(5D).5s 4D → 4d6.(5D).5p 4F* | Measured | NIST | |
| 409.5662 nm | 15000 | Tc I | emission | 4d6.(5D).5s 6D → 4d6.(5D).5p 6D* | Measured | NIST | |
| 408.8702 nm | 10000 | Tc I | emission | 4d6.(5D).5s 6D → 4d6.(5D).5p 6D* | Measured | NIST | |
| 411.5065 nm | 10000 | Tc I | emission | 4d6.(5D).5s 6D → 4d6.(5D).5p 6D* | Measured | NIST | |
| 416.5605 nm | 10000 | Tc I | emission | 4d6.(5D).5s 4D → 4d5.(6S).5s.(5S).5p 4P* | Measured | NIST | |
| 426.2245 nm | 10000 | Tc I | emission | 4d5.5s2 6S → 4d5.(6S).5s.(7S).5p 6P* | Measured | NIST | |
| 429.7034 nm | 10000 | Tc I | emission | 4d5.5s2 6S → 4d5.(6S).5s.(7S).5p 6P* | Measured | NIST | |
| 452.283 nm | 10000 | Tc I | emission | 4d6.(5D).5s 4D → 4d6.(5D).5p 4D* | Measured | NIST | |
| 474.0602 nm | 10000 | Tc I | emission | 4d6.(5D).5s 4D → 4d6.(5D).5p 4F* | Measured | NIST | |
| 482.0744 nm | 10000 | Tc I | emission | 4d5.(6S).5s.(7S).5p 8P* → 4d5.(6S).5s.(7S).6s e 8S | Measured | NIST | |
| 486.6732 nm | 10000 | Tc I | emission | 4d6.(5D).5s 4D → 4d6.(5D).5p 4F* | Measured | NIST | |
| 412.4217 nm | 8000 | Tc I | emission | 4d6.(5D).5s 6D → 4d6.(5D).5p 6D* | Measured | NIST | |
| 489.1909 nm | 8000 | Tc I | emission | 4d6.(5D).5s 4D → 4d6.(5D).5p 4F* | Measured | NIST | |
| 414.4961 nm | 6000 | Tc I | emission | 4d6.(5D).5s 6D → 4d6.(5D).5p 6D* | Measured | NIST | |
| 417.2523 nm | 5000 | Tc I | emission | 4d6.(5D).5s 6D → 4d6.(5D).5p 6D* | Measured | NIST | |
| 497.6341 nm | 5000 | Tc I | emission | 4d5.(6S).5s.(7S).5p 8P* → 4d5.(6S).5s.(7S).6s e 8S | Measured | NIST | |
| 509.6269 nm | 5000 | Tc I | emission | 4d6.(5D).5s 4D → 4d6.(5D).5p 6F* | Measured | NIST | |
| 417.0266 nm | 4000 | Tc I | emission | 4d6.(5D).5s 6D → 4d6.(5D).5p 6D* | Measured | NIST | |
| 477.1539 nm | 4000 | Tc I | emission | 4d6.(5D).5s 4D → 4d6.(5D).5p 4F* | Measured | NIST | |
| 414.5126 nm | 3000 | Tc I | emission | 4d6.(5D).5s 6D → 4d6.(5D).5p 6D* | Measured | NIST | |
| 448.7049 nm | 3000 | Tc I | emission | 4d6.(5D).5s 4D → 4d6.(5D).5p 4D* | Measured | NIST | |
| 463.7499 nm | 3000 | Tc I | emission | 4d6.(5D).5s 4D → 4d6.(5D).5p 4D* | Measured | NIST | |
| 394.709 nm | 2000 | Tc I | emission | 4d6.(3H).5s 4H → 4d6.(3H).5p 2I* | Measured | NIST | |
| 399.4498 nm | 2000 | Tc I | emission | 4d6.(3H).5s 4H → 4d6.(3H).5p 4G* | Measured | NIST | |
| 402.0759 nm | 2000 | Tc I | emission | 4d6.(3H).5s 2H → 4d6.(3H).5p 2H* | Measured | NIST | |
| 453.9513 nm | 2000 | Tc I | emission | 4d6.(5D).5s 4D → 4d6.(5D).5p 4D* | Measured | NIST | |
| 456.4541 nm | 2000 | Tc I | emission | 4d6.(5D).5s 4D → 4d6.(5D).5p 4D* | Measured | NIST | |
| 464.8328 nm | 2000 | Tc I | emission | 4d6.(5D).5s 4D → 4d6.(5D).5p 4D* | Measured | NIST | |
| 466.9303 nm | 2000 | Tc I | emission | 4d6.(5D).5s 4D → 4d6.(5D).5p 4P* | Measured | NIST | |
| 471.7758 nm | 2000 | Tc I | emission | 4d6.(5D).5s 4D → 4d6.(5D).5p 4F* | Measured | NIST | |
| 490.9509 nm | 2000 | Tc I | emission | 4d6.(5D).5s 4D → 4d6.(5D).5p 4F* | Measured | NIST | |
| 517.4813 nm | 2000 | Tc I | emission | 4d6.(5D).5s 4D → 4d6.(5D).5p 6F* | Measured | NIST | |
| 383.7565 nm | 1500 | Tc I | emission | 4d6.(3H).5s 4H → 4d6.(3H).5p 4I* | Measured | NIST | |
| 564.2116 nm | 1500 | Tc I | emission | 4d6.(3F2).5s 4F → 4d6.(5D).5p 4D* | Measured | NIST | |
| 386.8248 nm | 1000 | Tc I | emission | 4d6.(3H).5s 4H → 4d6.(3H).5p 4I* | Measured | NIST | |
| 401.1998 nm | 1000 | Tc I | emission | 4d6.(3H).5s 4H → 4d5.(4D).5s.(5D).5p 6F* | Measured | NIST | |
| 403.9232 nm | 1000 | Tc I | emission | 4d6.(3H).5s 4H → 4d6.(3H).5p 4G* | Measured | NIST | |
| 411.0214 nm | 1000 | Tc I | emission | 4d6.(1I).5s 2I → 4d6.(1I).5p 2K* | Measured | NIST | |
| 412.8263 nm | 1000 | Tc I | emission | 4d5.5s2 4G → 4d5.(4G).5s.(5G).5p 4H* | Measured | NIST | |
| 416.966 nm | 1000 | Tc I | emission | 4d6.(3H).5s 4H → 4d5.(4G).5s.(5G).5p 4H* | Measured | NIST | |
| 417.6253 nm | 1000 | Tc I | emission | 4d6.(5D).5s 6D → 4d6.(5D).5p 6D* | Measured | NIST | |
| 426.2682 nm | 1000 | Tc I | emission | 4d6.(5D).5s 4D → 4d5.(6S).5s.(5S).5p 4P* | Measured | NIST | |
| 442.9581 nm | 1000 | Tc I | emission | 4d6.(5D).5s 4D → 4d6.(5D).5p 4D* | Measured | NIST | |
| 448.1534 nm | 1000 | Tc I | emission | 4d6.(3H).5s 2H → 4d6.(3H).5p 4H* | Measured | NIST | |
| 451.5974 nm | 1000 | Tc I | emission | 4d6.(3H).5s 2H → 4d6.(3H).5p 4H* | Measured | NIST | |
| 455.7038 nm | 1000 | Tc I | emission | 4d6.(3F2).5s 4F → 4d6.(3F2).5p 4G* | Measured | NIST | |
| 457.8438 nm | 1000 | Tc I | emission | 4d6.(3G).5s 4G → 4d6.(3H).5p 2I* | Measured | NIST | |
| 459.3334 nm | 1000 | Tc I | emission | 4d6.(5D).5s 4D → 4d6.(5D).5p 4D* | Measured | NIST | |
| 461.6842 nm | 1000 | Tc I | emission | 4d5.(6S).5s.(7S).5p 6P* → 4d5.(6S).5s.(7S).5d f 6D | Measured | NIST | |
| 463.0527 nm | 1000 | Tc I | emission | 4d6.(5D).5s 4D → 4d6.(5D).5p 4D* | Measured | NIST |
Extended Properties
Covalent Radii (Extended)
- Covalent radius (Pyykkö)
- 128 pm
- Covalent radius (Pyykkö, double)
- 120 pm
- Covalent radius (Pyykkö, triple)
- 110 pm
Van der Waals Radii
- Batsanov
- 205 pm
- Alvarez
- 244 pm
- UFF
- 299.8 pm
- MM3
- 236 pm
Atomic & Metallic Radii
- Atomic radius (Rahm)
- 252 pm
- Metallic radius (C12)
- 136 pm
Numbering Scales
- Mendeleev
- 56
- Pettifor
- 58
- Glawe
- 59
Electronegativity Scales
- Ghosh
- 0
- Miedema
- 5
- Gunnarsson–Lundqvist
- 5
- Robles–Bartolotti
- 4
Polarizability & Dispersion
- Dipole polarizability
- 79 a.u.
- Dipole polarizability (unc.)
- 10 a.u.
- C₆ (Gould–Bučko)
- 939 Ha·Bohr6
Miedema Parameters
- Miedema molar volume
- 8.64 cm3/mol
- Miedema electron density
- 6
Phase Transitions & Allotropes
| Melting point | 2430.15 K |
| Boiling point | 4535.15 K |
Oxidation State Categories
Advanced Reference Data
Screening Constants (10)
| n | Orbital | σ |
|---|---|---|
| 1 | s | 0.891 |
| 2 | p | 4.0592 |
| 2 | s | 11.3718 |
| 3 | d | 14.647 |
| 3 | p | 16.6159 |
| 3 | s | 16.2088 |
| 4 | d | 30.118 |
| 4 | p | 27.1888 |
| 4 | s | 25.8016 |
| 5 | s | 35.7735 |
Crystal Radii Detail (4)
| Charge | CN | Spin | rcrystal (pm) | Origin |
|---|---|---|---|---|
| 4 | VI | 78.5 | from r^3 vs V plots, from metallic oxides, | |
| 5 | VI | 74 | estimated, from r^3 vs V plots, | |
| 7 | IV | 51 | ||
| 7 | VI | 70 | Ahrens (1952) ionic radius, |
Isotope Decay Modes (70)
| Isotope | Mode | Intensity |
|---|---|---|
| 83 | p | — |
| 83 | B+ | — |
| 83 | B+p | — |
| 84 | p | — |
| 84 | B+ | — |
| 84 | B+p | — |
| 85 | p | — |
| 86 | B+ | 100% |
| 86 | B+p | — |
| 87 | B+ | 100% |
X‑ray Scattering Factors (508)
| Energy (eV) | f₁ | f₂ |
|---|---|---|
| 10 | — | 1.1689 |
| 10.1617 | — | 1.2263 |
| 10.3261 | — | 1.28651 |
| 10.4931 | — | 1.34968 |
| 10.6628 | — | 1.41595 |
| 10.8353 | — | 1.48547 |
| 11.0106 | — | 1.55841 |
| 11.1886 | — | 1.63493 |
| 11.3696 | — | 1.7152 |
| 11.5535 | — | 1.7906 |
Additional Data
Estimated Crustal Abundance
The estimated element abundance in the earth's crust.
Not Applicable
References (1)
- [5] Technetium https://education.jlab.org/itselemental/ele043.html
Estimated Oceanic Abundance
The estimated element abundance in the earth's oceans.
Not Applicable
References (1)
- [5] Technetium https://education.jlab.org/itselemental/ele043.html
References
(9)
Data deposited in or computed by PubChem
The half-life and atomic mass data was provided by the Atomic Mass Data Center at the International Atomic Energy Agency.
Element data are cited from the Atomic weights of the elements (an IUPAC Technical Report). The IUPAC periodic table of elements can be found at https://iupac.org/what-we-do/periodic-table-of-elements/. Additional information can be found within IUPAC publication doi:10.1515/pac-2015-0703 Copyright © 2020 International Union of Pure and Applied Chemistry.
The information are cited from Pure Appl. Chem. 2018; 90(12): 1833-2092, https://doi.org/10.1515/pac-2015-0703.
Thomas Jefferson National Accelerator Facility (Jefferson Lab) is one of 17 national laboratories funded by the U.S. Department of Energy. The lab's primary mission is to conduct basic research of the atom's nucleus using the lab's unique particle accelerator, known as the Continuous Electron Beam Accelerator Facility (CEBAF). For more information visit https://www.jlab.org/
The periodic table at the LANL (Los Alamos National Laboratory) contains basic element information together with the history, source, properties, use, handling and more. The provenance data may be found from the link under the source name.
The periodic table contains NIST's critically-evaluated data on atomic properties of the elements. The provenance data that include data for atomic spectroscopy, X-ray and gamma ray, radiation dosimetry, nuclear physics, and condensed matter physics may be found from the link under the source name. Ref: https://www.nist.gov/pml/atomic-spectra-database
This section provides all form of data related to element Technetium.
The element property data was retrieved from publications.